Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

297 files changed, 41868 insertions, 0 deletions

diff --git a/dom/quota/ActorsChild.cpp b/dom/quota/ActorsChild.cpp
new file mode 100644
index 0000000000..071d13214c
--- /dev/null
+++ b/dom/quota/ActorsChild.cpp
@@ -0,0 +1,408 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ActorsChild.h"
+
+// Local includes
+#include "QuotaManagerService.h"
+#include "QuotaRequests.h"
+#include "QuotaResults.h"
+
+// Global includes
+#include <new>
+#include <utility>
+#include "mozilla/Assertions.h"
+#include "mozilla/dom/quota/PQuotaRequest.h"
+#include "mozilla/dom/quota/PQuotaUsageRequest.h"
+#include "nsError.h"
+#include "nsID.h"
+#include "nsIEventTarget.h"
+#include "nsIQuotaResults.h"
+#include "nsISupports.h"
+#include "nsIVariant.h"
+#include "nsString.h"
+#include "nsThreadUtils.h"
+#include "nsVariant.h"
+
+namespace mozilla::dom::quota {
+
+/*******************************************************************************
+ * QuotaChild
+ ******************************************************************************/
+
+QuotaChild::QuotaChild(QuotaManagerService* aService)
+    : mService(aService)
+#ifdef DEBUG
+      ,
+      mOwningThread(GetCurrentEventTarget())
+#endif
+{
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aService);
+
+  MOZ_COUNT_CTOR(quota::QuotaChild);
+}
+
+QuotaChild::~QuotaChild() {
+  AssertIsOnOwningThread();
+
+  MOZ_COUNT_DTOR(quota::QuotaChild);
+}
+
+#ifdef DEBUG
+
+void QuotaChild::AssertIsOnOwningThread() const {
+  MOZ_ASSERT(mOwningThread);
+
+  bool current;
+  MOZ_ASSERT(NS_SUCCEEDED(mOwningThread->IsOnCurrentThread(&current)));
+  MOZ_ASSERT(current);
+}
+
+#endif  // DEBUG
+
+void QuotaChild::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnOwningThread();
+
+  if (mService) {
+    mService->ClearBackgroundActor();
+#ifdef DEBUG
+    mService = nullptr;
+#endif
+  }
+}
+
+PQuotaUsageRequestChild* QuotaChild::AllocPQuotaUsageRequestChild(
+    const UsageRequestParams& aParams) {
+  AssertIsOnOwningThread();
+
+  MOZ_CRASH("PQuotaUsageRequestChild actors should be manually constructed!");
+}
+
+bool QuotaChild::DeallocPQuotaUsageRequestChild(
+    PQuotaUsageRequestChild* aActor) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aActor);
+
+  delete static_cast<QuotaUsageRequestChild*>(aActor);
+  return true;
+}
+
+PQuotaRequestChild* QuotaChild::AllocPQuotaRequestChild(
+    const RequestParams& aParams) {
+  AssertIsOnOwningThread();
+
+  MOZ_CRASH("PQuotaRequestChild actors should be manually constructed!");
+}
+
+bool QuotaChild::DeallocPQuotaRequestChild(PQuotaRequestChild* aActor) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aActor);
+
+  delete static_cast<QuotaRequestChild*>(aActor);
+  return true;
+}
+
+/*******************************************************************************
+ * QuotaUsageRequestChild
+ ******************************************************************************/
+
+QuotaUsageRequestChild::QuotaUsageRequestChild(UsageRequest* aRequest)
+    : mRequest(aRequest) {
+  AssertIsOnOwningThread();
+
+  MOZ_COUNT_CTOR(quota::QuotaUsageRequestChild);
+}
+
+QuotaUsageRequestChild::~QuotaUsageRequestChild() {
+  // Can't assert owning thread here because the request is cleared.
+
+  MOZ_COUNT_DTOR(quota::QuotaUsageRequestChild);
+}
+
+#ifdef DEBUG
+
+void QuotaUsageRequestChild::AssertIsOnOwningThread() const {
+  MOZ_ASSERT(mRequest);
+  mRequest->AssertIsOnOwningThread();
+}
+
+#endif  // DEBUG
+
+void QuotaUsageRequestChild::HandleResponse(nsresult aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(NS_FAILED(aResponse));
+  MOZ_ASSERT(mRequest);
+
+  mRequest->SetError(aResponse);
+}
+
+void QuotaUsageRequestChild::HandleResponse(
+    const nsTArray<OriginUsage>& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+
+  if (aResponse.IsEmpty()) {
+    variant->SetAsEmptyArray();
+  } else {
+    nsTArray<RefPtr<UsageResult>> usageResults(aResponse.Length());
+
+    for (const auto& originUsage : aResponse) {
+      usageResults.AppendElement(MakeRefPtr<UsageResult>(
+          originUsage.origin(), originUsage.persisted(), originUsage.usage(),
+          originUsage.lastAccessed()));
+    }
+
+    variant->SetAsArray(nsIDataType::VTYPE_INTERFACE_IS,
+                        &NS_GET_IID(nsIQuotaUsageResult), usageResults.Length(),
+                        static_cast<void*>(usageResults.Elements()));
+  }
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaUsageRequestChild::HandleResponse(
+    const OriginUsageResponse& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<OriginUsageResult> result =
+      new OriginUsageResult(aResponse.usage(), aResponse.fileUsage());
+
+  RefPtr<nsVariant> variant = new nsVariant();
+  variant->SetAsInterface(NS_GET_IID(nsIQuotaOriginUsageResult), result);
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaUsageRequestChild::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnOwningThread();
+
+  if (mRequest) {
+    mRequest->ClearBackgroundActor();
+#ifdef DEBUG
+    mRequest = nullptr;
+#endif
+  }
+}
+
+mozilla::ipc::IPCResult QuotaUsageRequestChild::Recv__delete__(
+    const UsageRequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  switch (aResponse.type()) {
+    case UsageRequestResponse::Tnsresult:
+      HandleResponse(aResponse.get_nsresult());
+      break;
+
+    case UsageRequestResponse::TAllUsageResponse:
+      HandleResponse(aResponse.get_AllUsageResponse().originUsages());
+      break;
+
+    case UsageRequestResponse::TOriginUsageResponse:
+      HandleResponse(aResponse.get_OriginUsageResponse());
+      break;
+
+    default:
+      MOZ_CRASH("Unknown response type!");
+  }
+
+  return IPC_OK();
+}
+
+/*******************************************************************************
+ * QuotaRequestChild
+ ******************************************************************************/
+
+QuotaRequestChild::QuotaRequestChild(Request* aRequest) : mRequest(aRequest) {
+  AssertIsOnOwningThread();
+
+  MOZ_COUNT_CTOR(quota::QuotaRequestChild);
+}
+
+QuotaRequestChild::~QuotaRequestChild() {
+  AssertIsOnOwningThread();
+
+  MOZ_COUNT_DTOR(quota::QuotaRequestChild);
+}
+
+#ifdef DEBUG
+
+void QuotaRequestChild::AssertIsOnOwningThread() const {
+  MOZ_ASSERT(mRequest);
+  mRequest->AssertIsOnOwningThread();
+}
+
+#endif  // DEBUG
+
+void QuotaRequestChild::HandleResponse(nsresult aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(NS_FAILED(aResponse));
+  MOZ_ASSERT(mRequest);
+
+  mRequest->SetError(aResponse);
+}
+
+void QuotaRequestChild::HandleResponse() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+  variant->SetAsVoid();
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::HandleResponse(bool aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+  variant->SetAsBool(aResponse);
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::HandleResponse(const nsAString& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+  variant->SetAsAString(aResponse);
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::HandleResponse(const EstimateResponse& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<EstimateResult> result =
+      new EstimateResult(aResponse.usage(), aResponse.limit());
+
+  RefPtr<nsVariant> variant = new nsVariant();
+  variant->SetAsInterface(NS_GET_IID(nsIQuotaEstimateResult), result);
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::HandleResponse(const nsTArray<nsCString>& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+
+  if (aResponse.IsEmpty()) {
+    variant->SetAsEmptyArray();
+  } else {
+    nsTArray<const char*> stringPointers(aResponse.Length());
+    std::transform(aResponse.cbegin(), aResponse.cend(),
+                   MakeBackInserter(stringPointers),
+                   std::mem_fn(&nsCString::get));
+
+    variant->SetAsArray(nsIDataType::VTYPE_CHAR_STR, nullptr,
+                        stringPointers.Length(), stringPointers.Elements());
+  }
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::HandleResponse(
+    const GetFullOriginMetadataResponse& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  RefPtr<nsVariant> variant = new nsVariant();
+
+  if (aResponse.maybeFullOriginMetadata()) {
+    RefPtr<FullOriginMetadataResult> result =
+        new FullOriginMetadataResult(*aResponse.maybeFullOriginMetadata());
+
+    variant->SetAsInterface(NS_GET_IID(nsIQuotaFullOriginMetadataResult),
+                            result);
+
+  } else {
+    variant->SetAsVoid();
+  }
+
+  mRequest->SetResult(variant);
+}
+
+void QuotaRequestChild::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnOwningThread();
+}
+
+mozilla::ipc::IPCResult QuotaRequestChild::Recv__delete__(
+    const RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mRequest);
+
+  switch (aResponse.type()) {
+    case RequestResponse::Tnsresult:
+      HandleResponse(aResponse.get_nsresult());
+      break;
+
+    case RequestResponse::TStorageNameResponse:
+      HandleResponse(aResponse.get_StorageNameResponse().name());
+      break;
+
+    case RequestResponse::TStorageInitializedResponse:
+      HandleResponse(aResponse.get_StorageInitializedResponse().initialized());
+      break;
+
+    case RequestResponse::TTemporaryStorageInitializedResponse:
+      HandleResponse(
+          aResponse.get_TemporaryStorageInitializedResponse().initialized());
+      break;
+
+    case RequestResponse::TInitResponse:
+    case RequestResponse::TInitTemporaryStorageResponse:
+    case RequestResponse::TClearOriginResponse:
+    case RequestResponse::TResetOriginResponse:
+    case RequestResponse::TClearDataResponse:
+    case RequestResponse::TClearAllResponse:
+    case RequestResponse::TResetAllResponse:
+    case RequestResponse::TPersistResponse:
+      HandleResponse();
+      break;
+
+    case RequestResponse::TInitializePersistentOriginResponse:
+      HandleResponse(
+          aResponse.get_InitializePersistentOriginResponse().created());
+      break;
+
+    case RequestResponse::TInitializeTemporaryOriginResponse:
+      HandleResponse(
+          aResponse.get_InitializeTemporaryOriginResponse().created());
+      break;
+
+    case RequestResponse::TGetFullOriginMetadataResponse:
+      HandleResponse(aResponse.get_GetFullOriginMetadataResponse());
+      break;
+
+    case RequestResponse::TPersistedResponse:
+      HandleResponse(aResponse.get_PersistedResponse().persisted());
+      break;
+
+    case RequestResponse::TEstimateResponse:
+      HandleResponse(aResponse.get_EstimateResponse());
+      break;
+
+    case RequestResponse::TListOriginsResponse:
+      HandleResponse(aResponse.get_ListOriginsResponse().origins());
+      break;
+
+    default:
+      MOZ_CRASH("Unknown response type!");
+  }
+
+  return IPC_OK();
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/ActorsChild.h b/dom/quota/ActorsChild.h
new file mode 100644
index 0000000000..df1881b234
--- /dev/null
+++ b/dom/quota/ActorsChild.h
@@ -0,0 +1,158 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_ActorsChild_h
+#define mozilla_dom_quota_ActorsChild_h
+
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/dom/quota/PQuotaChild.h"
+#include "mozilla/dom/quota/PQuotaRequestChild.h"
+#include "mozilla/dom/quota/PQuotaUsageRequestChild.h"
+#include "mozilla/ipc/ProtocolUtils.h"
+#include "nsCOMPtr.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+
+class nsIEventTarget;
+
+namespace mozilla {
+namespace ipc {
+
+class BackgroundChildImpl;
+
+}  // namespace ipc
+
+namespace dom::quota {
+
+class QuotaManagerService;
+class Request;
+class UsageRequest;
+
+class QuotaChild final : public PQuotaChild {
+  friend class mozilla::ipc::BackgroundChildImpl;
+  friend class QuotaManagerService;
+
+  QuotaManagerService* mService;
+
+#ifdef DEBUG
+  nsCOMPtr<nsIEventTarget> mOwningThread;
+#endif
+
+ public:
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+ private:
+  // Only created by QuotaManagerService.
+  explicit QuotaChild(QuotaManagerService* aService);
+
+  // Only destroyed by mozilla::ipc::BackgroundChildImpl.
+  ~QuotaChild();
+
+  // IPDL methods are only called by IPDL.
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  virtual PQuotaUsageRequestChild* AllocPQuotaUsageRequestChild(
+      const UsageRequestParams& aParams) override;
+
+  virtual bool DeallocPQuotaUsageRequestChild(
+      PQuotaUsageRequestChild* aActor) override;
+
+  virtual PQuotaRequestChild* AllocPQuotaRequestChild(
+      const RequestParams& aParams) override;
+
+  virtual bool DeallocPQuotaRequestChild(PQuotaRequestChild* aActor) override;
+};
+
+class QuotaUsageRequestChild final : public PQuotaUsageRequestChild {
+  friend class QuotaChild;
+  friend class QuotaManagerService;
+
+  RefPtr<UsageRequest> mRequest;
+
+ public:
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+ private:
+  // Only created by QuotaManagerService.
+  explicit QuotaUsageRequestChild(UsageRequest* aRequest);
+
+  // Only destroyed by QuotaChild.
+  ~QuotaUsageRequestChild();
+
+  void HandleResponse(nsresult aResponse);
+
+  void HandleResponse(const nsTArray<OriginUsage>& aResponse);
+
+  void HandleResponse(const OriginUsageResponse& aResponse);
+
+  // IPDL methods are only called by IPDL.
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  virtual mozilla::ipc::IPCResult Recv__delete__(
+      const UsageRequestResponse& aResponse) override;
+};
+
+class QuotaRequestChild final : public PQuotaRequestChild {
+  friend class QuotaChild;
+  friend class QuotaManagerService;
+
+  RefPtr<Request> mRequest;
+
+ public:
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+ private:
+  // Only created by QuotaManagerService.
+  explicit QuotaRequestChild(Request* aRequest);
+
+  // Only destroyed by QuotaChild.
+  ~QuotaRequestChild();
+
+  void HandleResponse(nsresult aResponse);
+
+  void HandleResponse();
+
+  void HandleResponse(bool aResponse);
+
+  void HandleResponse(const nsAString& aResponse);
+
+  void HandleResponse(const EstimateResponse& aResponse);
+
+  void HandleResponse(const nsTArray<nsCString>& aResponse);
+
+  void HandleResponse(const GetFullOriginMetadataResponse& aResponse);
+
+  // IPDL methods are only called by IPDL.
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  virtual mozilla::ipc::IPCResult Recv__delete__(
+      const RequestResponse& aResponse) override;
+};
+
+}  // namespace dom::quota
+}  // namespace mozilla
+
+#endif  // mozilla_dom_quota_ActorsChild_h
diff --git a/dom/quota/ActorsParent.cpp b/dom/quota/ActorsParent.cpp
new file mode 100644
index 0000000000..ec1507b05d
--- /dev/null
+++ b/dom/quota/ActorsParent.cpp
@@ -0,0 +1,10856 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ActorsParent.h"
+
+// Local includes
+#include "CanonicalQuotaObject.h"
+#include "ClientUsageArray.h"
+#include "Flatten.h"
+#include "FirstInitializationAttemptsImpl.h"
+#include "GroupInfo.h"
+#include "GroupInfoPair.h"
+#include "OriginScope.h"
+#include "OriginInfo.h"
+#include "QuotaCommon.h"
+#include "QuotaManager.h"
+#include "ScopedLogExtraInfo.h"
+#include "UsageInfo.h"
+
+// Global includes
+#include <cinttypes>
+#include <cstdlib>
+#include <cstring>
+#include <algorithm>
+#include <cstdint>
+#include <functional>
+#include <new>
+#include <numeric>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+#include "DirectoryLockImpl.h"
+#include "ErrorList.h"
+#include "MainThreadUtils.h"
+#include "mozIStorageAsyncConnection.h"
+#include "mozIStorageConnection.h"
+#include "mozIStorageService.h"
+#include "mozIStorageStatement.h"
+#include "mozStorageCID.h"
+#include "mozStorageHelper.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/AppShutdown.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/AutoRestore.h"
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/CheckedInt.h"
+#include "mozilla/CondVar.h"
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/Logging.h"
+#include "mozilla/MacroForEach.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/NotNull.h"
+#include "mozilla/OriginAttributes.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/ProfilerLabels.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/ScopeExit.h"
+#include "mozilla/Services.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TelemetryHistogramEnums.h"
+#include "mozilla/TextUtils.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Unused.h"
+#include "mozilla/Variant.h"
+#include "mozilla/dom/FileSystemQuotaClient.h"
+#include "mozilla/dom/FlippedOnce.h"
+#include "mozilla/dom/LocalStorageCommon.h"
+#include "mozilla/dom/StorageDBUpdater.h"
+#include "mozilla/dom/cache/QuotaClient.h"
+#include "mozilla/dom/indexedDB/ActorsParent.h"
+#include "mozilla/dom/ipc/IdType.h"
+#include "mozilla/dom/localstorage/ActorsParent.h"
+#include "mozilla/dom/quota/AssertionsImpl.h"
+#include "mozilla/dom/quota/CheckedUnsafePtr.h"
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/DirectoryLock.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "mozilla/dom/quota/PQuota.h"
+#include "mozilla/dom/quota/PQuotaParent.h"
+#include "mozilla/dom/quota/PQuotaRequest.h"
+#include "mozilla/dom/quota/PQuotaRequestParent.h"
+#include "mozilla/dom/quota/PQuotaUsageRequest.h"
+#include "mozilla/dom/quota/PQuotaUsageRequestParent.h"
+#include "mozilla/dom/quota/QuotaManagerImpl.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/dom/quota/ScopedLogExtraInfo.h"
+#include "mozilla/dom/simpledb/ActorsParent.h"
+#include "mozilla/fallible.h"
+#include "mozilla/ipc/BackgroundChild.h"
+#include "mozilla/ipc/BackgroundParent.h"
+#include "mozilla/ipc/PBackgroundChild.h"
+#include "mozilla/ipc/PBackgroundSharedTypes.h"
+#include "mozilla/ipc/ProtocolUtils.h"
+#include "mozilla/net/MozURL.h"
+#include "nsAppDirectoryServiceDefs.h"
+#include "nsBaseHashtable.h"
+#include "nsCOMPtr.h"
+#include "nsCRTGlue.h"
+#include "nsCharSeparatedTokenizer.h"
+#include "nsClassHashtable.h"
+#include "nsComponentManagerUtils.h"
+#include "nsContentUtils.h"
+#include "nsTHashMap.h"
+#include "nsDebug.h"
+#include "nsDirectoryServiceUtils.h"
+#include "nsError.h"
+#include "nsHashKeys.h"
+#include "nsIBinaryInputStream.h"
+#include "nsIBinaryOutputStream.h"
+#include "nsIConsoleService.h"
+#include "nsIDirectoryEnumerator.h"
+#include "nsIEventTarget.h"
+#include "nsIFile.h"
+#include "nsIFileStreams.h"
+#include "nsIInputStream.h"
+#include "nsIObjectInputStream.h"
+#include "nsIObjectOutputStream.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsIOutputStream.h"
+#include "nsIPlatformInfo.h"
+#include "nsIPrincipal.h"
+#include "nsIRunnable.h"
+#include "nsIScriptObjectPrincipal.h"
+#include "nsISupports.h"
+#include "nsISupportsPrimitives.h"
+#include "nsIThread.h"
+#include "nsITimer.h"
+#include "nsIURI.h"
+#include "nsIWidget.h"
+#include "nsLiteralString.h"
+#include "nsNetUtil.h"
+#include "nsPIDOMWindow.h"
+#include "nsPrintfCString.h"
+#include "nsServiceManagerUtils.h"
+#include "nsString.h"
+#include "nsStringFlags.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nsTHashtable.h"
+#include "nsTLiteralString.h"
+#include "nsTPromiseFlatString.h"
+#include "nsTStringRepr.h"
+#include "nsThreadUtils.h"
+#include "nsURLHelper.h"
+#include "nsXPCOM.h"
+#include "nsXPCOMCID.h"
+#include "nsXULAppAPI.h"
+#include "prinrval.h"
+#include "prio.h"
+#include "prthread.h"
+#include "prtime.h"
+
+// As part of bug 1536596 in order to identify the remaining sources of
+// principal info inconsistencies, we have added anonymized crash logging and
+// are temporarily making these checks occur on both debug and optimized
+// nightly, dev-edition, and early beta builds through use of
+// EARLY_BETA_OR_EARLIER during Firefox 82.  The plan is to return this
+// condition to MOZ_DIAGNOSTIC_ASSERT_ENABLED during Firefox 84 at the latest.
+// The analysis and disabling is tracked by bug 1536596.
+
+#ifdef EARLY_BETA_OR_EARLIER
+#  define QM_PRINCIPALINFO_VERIFICATION_ENABLED
+#endif
+
+// The amount of time, in milliseconds, that our IO thread will stay alive
+// after the last event it processes.
+#define DEFAULT_THREAD_TIMEOUT_MS 30000
+
+/**
+ * If shutdown takes this long, kill actors of a quota client, to avoid reaching
+ * the crash timeout.
+ */
+#define SHUTDOWN_KILL_ACTORS_TIMEOUT_MS 5000
+
+/**
+ * Automatically crash the browser if shutdown of a quota client takes this
+ * long. We've chosen a value that is long enough that it is unlikely for the
+ * problem to be falsely triggered by slow system I/O.  We've also chosen a
+ * value long enough so that automated tests should time out and fail if
+ * shutdown of a quota client takes too long.  Also, this value is long enough
+ * so that testers can notice the timeout; we want to know about the timeouts,
+ * not hide them. On the other hand this value is less than 60 seconds which is
+ * used by nsTerminator to crash a hung main process.
+ */
+#define SHUTDOWN_CRASH_BROWSER_TIMEOUT_MS 45000
+
+static_assert(
+    SHUTDOWN_CRASH_BROWSER_TIMEOUT_MS > SHUTDOWN_KILL_ACTORS_TIMEOUT_MS,
+    "The kill actors timeout must be shorter than the crash browser one.");
+
+// profile-before-change, when we need to shut down quota manager
+#define PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID "profile-before-change-qm"
+
+#define KB *1024ULL
+#define MB *1024ULL KB
+#define GB *1024ULL MB
+
+namespace mozilla::dom::quota {
+
+using namespace mozilla::ipc;
+using mozilla::net::MozURL;
+
+// We want profiles to be platform-independent so we always need to replace
+// the same characters on every platform. Windows has the most extensive set
+// of illegal characters so we use its FILE_ILLEGAL_CHARACTERS and
+// FILE_PATH_SEPARATOR.
+const char QuotaManager::kReplaceChars[] = CONTROL_CHARACTERS "/:*?\"<>|\\";
+const char16_t QuotaManager::kReplaceChars16[] =
+    u"" CONTROL_CHARACTERS "/:*?\"<>|\\";
+
+namespace {
+
+/*******************************************************************************
+ * Constants
+ ******************************************************************************/
+
+const uint32_t kSQLitePageSizeOverride = 512;
+
+// Important version history:
+// - Bug 1290481 bumped our schema from major.minor 2.0 to 3.0 in Firefox 57
+//   which caused Firefox 57 release concerns because the major schema upgrade
+//   means anyone downgrading to Firefox 56 will experience a non-operational
+//   QuotaManager and all of its clients.
+// - Bug 1404344 got very concerned about that and so we decided to effectively
+//   rename 3.0 to 2.1, effective in Firefox 57.  This works because post
+//   storage.sqlite v1.0, QuotaManager doesn't care about minor storage version
+//   increases.  It also works because all the upgrade did was give the DOM
+//   Cache API QuotaClient an opportunity to create its newly added .padding
+//   files during initialization/upgrade, which isn't functionally necessary as
+//   that can be done on demand.
+
+// Major storage version. Bump for backwards-incompatible changes.
+// (The next major version should be 4 to distinguish from the Bug 1290481
+// downgrade snafu.)
+const uint32_t kMajorStorageVersion = 2;
+
+// Minor storage version. Bump for backwards-compatible changes.
+const uint32_t kMinorStorageVersion = 3;
+
+// The storage version we store in the SQLite database is a (signed) 32-bit
+// integer. The major version is left-shifted 16 bits so the max value is
+// 0xFFFF. The minor version occupies the lower 16 bits and its max is 0xFFFF.
+static_assert(kMajorStorageVersion <= 0xFFFF,
+              "Major version needs to fit in 16 bits.");
+static_assert(kMinorStorageVersion <= 0xFFFF,
+              "Minor version needs to fit in 16 bits.");
+
+const int32_t kStorageVersion =
+    int32_t((kMajorStorageVersion << 16) + kMinorStorageVersion);
+
+// See comments above about why these are a thing.
+const int32_t kHackyPreDowngradeStorageVersion = int32_t((3 << 16) + 0);
+const int32_t kHackyPostDowngradeStorageVersion = int32_t((2 << 16) + 1);
+
+const char kChromeOrigin[] = "chrome";
+const char kAboutHomeOriginPrefix[] = "moz-safe-about:home";
+const char kIndexedDBOriginPrefix[] = "indexeddb://";
+const char kResourceOriginPrefix[] = "resource://";
+
+constexpr auto kStorageName = u"storage"_ns;
+constexpr auto kSQLiteSuffix = u".sqlite"_ns;
+
+#define INDEXEDDB_DIRECTORY_NAME u"indexedDB"
+#define ARCHIVES_DIRECTORY_NAME u"archives"
+#define PERSISTENT_DIRECTORY_NAME u"persistent"
+#define PERMANENT_DIRECTORY_NAME u"permanent"
+#define TEMPORARY_DIRECTORY_NAME u"temporary"
+#define DEFAULT_DIRECTORY_NAME u"default"
+
+// The name of the file that we use to load/save the last access time of an
+// origin.
+// XXX We should get rid of old metadata files at some point, bug 1343576.
+#define METADATA_FILE_NAME u".metadata"
+#define METADATA_TMP_FILE_NAME u".metadata-tmp"
+#define METADATA_V2_FILE_NAME u".metadata-v2"
+#define METADATA_V2_TMP_FILE_NAME u".metadata-v2-tmp"
+
+#define WEB_APPS_STORE_FILE_NAME u"webappsstore.sqlite"
+#define LS_ARCHIVE_FILE_NAME u"ls-archive.sqlite"
+#define LS_ARCHIVE_TMP_FILE_NAME u"ls-archive-tmp.sqlite"
+
+const int32_t kLocalStorageArchiveVersion = 4;
+
+const char kProfileDoChangeTopic[] = "profile-do-change";
+
+const int32_t kCacheVersion = 2;
+
+/******************************************************************************
+ * SQLite functions
+ ******************************************************************************/
+
+int32_t MakeStorageVersion(uint32_t aMajorStorageVersion,
+                           uint32_t aMinorStorageVersion) {
+  return int32_t((aMajorStorageVersion << 16) + aMinorStorageVersion);
+}
+
+uint32_t GetMajorStorageVersion(int32_t aStorageVersion) {
+  return uint32_t(aStorageVersion >> 16);
+}
+
+nsresult CreateTables(mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  // Table `database`
+  QM_TRY(MOZ_TO_RESULT(
+      aConnection->ExecuteSimpleSQL("CREATE TABLE database"
+                                    "( cache_version INTEGER NOT NULL DEFAULT 0"
+                                    ");"_ns)));
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const int32_t& storageVersion,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, GetSchemaVersion));
+
+    MOZ_ASSERT(storageVersion == 0);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(aConnection->SetSchemaVersion(kStorageVersion)));
+
+  return NS_OK;
+}
+
+Result<int32_t, nsresult> LoadCacheVersion(mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& stmt,
+                 CreateAndExecuteSingleStepStatement<
+                     SingleStepResult::ReturnNullIfNoResult>(
+                     aConnection, "SELECT cache_version FROM database"_ns));
+
+  QM_TRY(OkIf(stmt), Err(NS_ERROR_FILE_CORRUPTED));
+
+  QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 0));
+}
+
+nsresult SaveCacheVersion(mozIStorageConnection& aConnection,
+                          int32_t aVersion) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(
+      const auto& stmt,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+          nsCOMPtr<mozIStorageStatement>, aConnection, CreateStatement,
+          "UPDATE database SET cache_version = :version;"_ns));
+
+  QM_TRY(MOZ_TO_RESULT(stmt->BindInt32ByName("version"_ns, aVersion)));
+
+  QM_TRY(MOZ_TO_RESULT(stmt->Execute()));
+
+  return NS_OK;
+}
+
+nsresult CreateCacheTables(mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  // Table `cache`
+  QM_TRY(MOZ_TO_RESULT(
+      aConnection.ExecuteSimpleSQL("CREATE TABLE cache"
+                                   "( valid INTEGER NOT NULL DEFAULT 0"
+                                   ", build_id TEXT NOT NULL DEFAULT ''"
+                                   ");"_ns)));
+
+  // Table `repository`
+  QM_TRY(
+      MOZ_TO_RESULT(aConnection.ExecuteSimpleSQL("CREATE TABLE repository"
+                                                 "( id INTEGER PRIMARY KEY"
+                                                 ", name TEXT NOT NULL"
+                                                 ");"_ns)));
+
+  // Table `origin`
+  QM_TRY(MOZ_TO_RESULT(
+      aConnection.ExecuteSimpleSQL("CREATE TABLE origin"
+                                   "( repository_id INTEGER NOT NULL"
+                                   ", suffix TEXT"
+                                   ", group_ TEXT NOT NULL"
+                                   ", origin TEXT NOT NULL"
+                                   ", client_usages TEXT NOT NULL"
+                                   ", usage INTEGER NOT NULL"
+                                   ", last_access_time INTEGER NOT NULL"
+                                   ", accessed INTEGER NOT NULL"
+                                   ", persisted INTEGER NOT NULL"
+                                   ", PRIMARY KEY (repository_id, origin)"
+                                   ", FOREIGN KEY (repository_id) "
+                                   "REFERENCES repository(id) "
+                                   ");"_ns)));
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const int32_t& cacheVersion, LoadCacheVersion(aConnection));
+    MOZ_ASSERT(cacheVersion == 0);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(SaveCacheVersion(aConnection, kCacheVersion)));
+
+  return NS_OK;
+}
+
+OkOrErr InvalidateCache(mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  static constexpr auto kDeleteCacheQuery = "DELETE FROM origin;"_ns;
+  static constexpr auto kSetInvalidFlagQuery = "UPDATE cache SET valid = 0"_ns;
+
+  QM_TRY(QM_OR_ELSE_WARN(
+      // Expression.
+      ([&]() -> OkOrErr {
+        mozStorageTransaction transaction(&aConnection,
+                                          /*aCommitOnComplete */ false);
+
+        QM_TRY(QM_TO_RESULT(transaction.Start()));
+        QM_TRY(QM_TO_RESULT(aConnection.ExecuteSimpleSQL(kDeleteCacheQuery)));
+        QM_TRY(
+            QM_TO_RESULT(aConnection.ExecuteSimpleSQL(kSetInvalidFlagQuery)));
+        QM_TRY(QM_TO_RESULT(transaction.Commit()));
+
+        return Ok{};
+      }()),
+      // Fallback.
+      ([&](const QMResult& rv) -> OkOrErr {
+        QM_TRY(
+            QM_TO_RESULT(aConnection.ExecuteSimpleSQL(kSetInvalidFlagQuery)));
+
+        return Ok{};
+      })));
+
+  return Ok{};
+}
+
+nsresult UpgradeCacheFrom1To2(mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  QM_TRY(MOZ_TO_RESULT(aConnection.ExecuteSimpleSQL(
+      "ALTER TABLE origin ADD COLUMN suffix TEXT"_ns)));
+
+  QM_TRY(InvalidateCache(aConnection));
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const int32_t& cacheVersion, LoadCacheVersion(aConnection));
+
+    MOZ_ASSERT(cacheVersion == 1);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(SaveCacheVersion(aConnection, 2)));
+
+  return NS_OK;
+}
+
+Result<bool, nsresult> MaybeCreateOrUpgradeCache(
+    mozIStorageConnection& aConnection) {
+  bool cacheUsable = true;
+
+  QM_TRY_UNWRAP(int32_t cacheVersion, LoadCacheVersion(aConnection));
+
+  if (cacheVersion > kCacheVersion) {
+    cacheUsable = false;
+  } else if (cacheVersion != kCacheVersion) {
+    const bool newCache = !cacheVersion;
+
+    mozStorageTransaction transaction(
+        &aConnection, false, mozIStorageConnection::TRANSACTION_IMMEDIATE);
+
+    QM_TRY(MOZ_TO_RESULT(transaction.Start()));
+
+    if (newCache) {
+      QM_TRY(MOZ_TO_RESULT(CreateCacheTables(aConnection)));
+
+#ifdef DEBUG
+      {
+        QM_TRY_INSPECT(const int32_t& cacheVersion,
+                       LoadCacheVersion(aConnection));
+        MOZ_ASSERT(cacheVersion == kCacheVersion);
+      }
+#endif
+
+      QM_TRY(MOZ_TO_RESULT(aConnection.ExecuteSimpleSQL(
+          nsLiteralCString("INSERT INTO cache (valid, build_id) "
+                           "VALUES (0, '')"))));
+
+      nsCOMPtr<mozIStorageStatement> insertStmt;
+
+      for (const PersistenceType persistenceType : kAllPersistenceTypes) {
+        if (insertStmt) {
+          MOZ_ALWAYS_SUCCEEDS(insertStmt->Reset());
+        } else {
+          QM_TRY_UNWRAP(insertStmt, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                        nsCOMPtr<mozIStorageStatement>,
+                                        aConnection, CreateStatement,
+                                        "INSERT INTO repository (id, name) "
+                                        "VALUES (:id, :name)"_ns));
+        }
+
+        QM_TRY(MOZ_TO_RESULT(
+            insertStmt->BindInt32ByName("id"_ns, persistenceType)));
+
+        QM_TRY(MOZ_TO_RESULT(insertStmt->BindUTF8StringByName(
+            "name"_ns, PersistenceTypeToString(persistenceType))));
+
+        QM_TRY(MOZ_TO_RESULT(insertStmt->Execute()));
+      }
+    } else {
+      // This logic needs to change next time we change the cache!
+      static_assert(kCacheVersion == 2,
+                    "Upgrade function needed due to cache version increase.");
+
+      while (cacheVersion != kCacheVersion) {
+        if (cacheVersion == 1) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeCacheFrom1To2(aConnection)));
+        } else {
+          QM_FAIL(Err(NS_ERROR_FAILURE), []() {
+            QM_WARNING(
+                "Unable to initialize cache, no upgrade path is "
+                "available!");
+          });
+        }
+
+        QM_TRY_UNWRAP(cacheVersion, LoadCacheVersion(aConnection));
+      }
+
+      MOZ_ASSERT(cacheVersion == kCacheVersion);
+    }
+
+    QM_TRY(MOZ_TO_RESULT(transaction.Commit()));
+  }
+
+  return cacheUsable;
+}
+
+Result<nsCOMPtr<mozIStorageConnection>, nsresult> CreateWebAppsStoreConnection(
+    nsIFile& aWebAppsStoreFile, mozIStorageService& aStorageService) {
+  AssertIsOnIOThread();
+
+  // Check if the old database exists at all.
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aWebAppsStoreFile, Exists));
+
+  if (!exists) {
+    // webappsstore.sqlite doesn't exist, return a null connection.
+    return nsCOMPtr<mozIStorageConnection>{};
+  }
+
+  QM_TRY_INSPECT(const bool& isDirectory,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aWebAppsStoreFile, IsDirectory));
+
+  if (isDirectory) {
+    QM_WARNING("webappsstore.sqlite is not a file!");
+    return nsCOMPtr<mozIStorageConnection>{};
+  }
+
+  QM_TRY_INSPECT(const auto& connection,
+                 QM_OR_ELSE_WARN_IF(
+                     // Expression.
+                     MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                         nsCOMPtr<mozIStorageConnection>, aStorageService,
+                         OpenUnsharedDatabase, &aWebAppsStoreFile,
+                         mozIStorageService::CONNECTION_DEFAULT),
+                     // Predicate.
+                     IsDatabaseCorruptionError,
+                     // Fallback. Don't throw an error, leave a corrupted
+                     // webappsstore database as it is.
+                     ErrToDefaultOk<nsCOMPtr<mozIStorageConnection>>));
+
+  if (connection) {
+    // Don't propagate an error, leave a non-updateable webappsstore database as
+    // it is.
+    QM_TRY(MOZ_TO_RESULT(StorageDBUpdater::Update(connection)),
+           nsCOMPtr<mozIStorageConnection>{});
+  }
+
+  return connection;
+}
+
+Result<nsCOMPtr<nsIFile>, QMResult> GetLocalStorageArchiveFile(
+    const nsAString& aDirectoryPath) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!aDirectoryPath.IsEmpty());
+
+  QM_TRY_UNWRAP(auto lsArchiveFile,
+                QM_TO_RESULT_TRANSFORM(QM_NewLocalFile(aDirectoryPath)));
+
+  QM_TRY(QM_TO_RESULT(
+      lsArchiveFile->Append(nsLiteralString(LS_ARCHIVE_FILE_NAME))));
+
+  return lsArchiveFile;
+}
+
+Result<nsCOMPtr<nsIFile>, nsresult> GetLocalStorageArchiveTmpFile(
+    const nsAString& aDirectoryPath) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!aDirectoryPath.IsEmpty());
+
+  QM_TRY_UNWRAP(auto lsArchiveTmpFile, QM_NewLocalFile(aDirectoryPath));
+
+  QM_TRY(MOZ_TO_RESULT(
+      lsArchiveTmpFile->Append(nsLiteralString(LS_ARCHIVE_TMP_FILE_NAME))));
+
+  return lsArchiveTmpFile;
+}
+
+Result<bool, nsresult> IsLocalStorageArchiveInitialized(
+    mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  QM_TRY_RETURN(
+      MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, TableExists, "database"_ns));
+}
+
+nsresult InitializeLocalStorageArchive(mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const auto& initialized,
+                   IsLocalStorageArchiveInitialized(*aConnection));
+    MOZ_ASSERT(!initialized);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(aConnection->ExecuteSimpleSQL(
+      "CREATE TABLE database(version INTEGER NOT NULL DEFAULT 0);"_ns)));
+
+  QM_TRY_INSPECT(
+      const auto& stmt,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+          nsCOMPtr<mozIStorageStatement>, aConnection, CreateStatement,
+          "INSERT INTO database (version) VALUES (:version)"_ns));
+
+  QM_TRY(MOZ_TO_RESULT(stmt->BindInt32ByName("version"_ns, 0)));
+  QM_TRY(MOZ_TO_RESULT(stmt->Execute()));
+
+  return NS_OK;
+}
+
+Result<int32_t, nsresult> LoadLocalStorageArchiveVersion(
+    mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& stmt,
+                 CreateAndExecuteSingleStepStatement<
+                     SingleStepResult::ReturnNullIfNoResult>(
+                     aConnection, "SELECT version FROM database"_ns));
+
+  QM_TRY(OkIf(stmt), Err(NS_ERROR_FILE_CORRUPTED));
+
+  QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 0));
+}
+
+nsresult SaveLocalStorageArchiveVersion(mozIStorageConnection* aConnection,
+                                        int32_t aVersion) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = aConnection->CreateStatement(
+      "UPDATE database SET version = :version;"_ns, getter_AddRefs(stmt));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = stmt->BindInt32ByName("version"_ns, aVersion);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = stmt->Execute();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+template <typename FileFunc, typename DirectoryFunc>
+Result<mozilla::Ok, nsresult> CollectEachFileEntry(
+    nsIFile& aDirectory, const FileFunc& aFileFunc,
+    const DirectoryFunc& aDirectoryFunc) {
+  AssertIsOnIOThread();
+
+  return CollectEachFile(
+      aDirectory,
+      [&aFileFunc, &aDirectoryFunc](
+          const nsCOMPtr<nsIFile>& file) -> Result<mozilla::Ok, nsresult> {
+        QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*file));
+
+        switch (dirEntryKind) {
+          case nsIFileKind::ExistsAsDirectory:
+            return aDirectoryFunc(file);
+
+          case nsIFileKind::ExistsAsFile:
+            return aFileFunc(file);
+
+          case nsIFileKind::DoesNotExist:
+            // Ignore files that got removed externally while iterating.
+            break;
+        }
+
+        return Ok{};
+      });
+}
+
+/******************************************************************************
+ * Quota manager class declarations
+ ******************************************************************************/
+
+}  // namespace
+
+class QuotaManager::Observer final : public nsIObserver {
+  static Observer* sInstance;
+
+  bool mPendingProfileChange;
+  bool mShutdownComplete;
+
+ public:
+  static nsresult Initialize();
+
+  static nsIObserver* GetInstance();
+
+  static void ShutdownCompleted();
+
+ private:
+  Observer() : mPendingProfileChange(false), mShutdownComplete(false) {
+    MOZ_ASSERT(NS_IsMainThread());
+  }
+
+  ~Observer() { MOZ_ASSERT(NS_IsMainThread()); }
+
+  nsresult Init();
+
+  nsresult Shutdown();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+};
+
+namespace {
+
+/*******************************************************************************
+ * Local class declarations
+ ******************************************************************************/
+
+}  // namespace
+
+namespace {
+
+class CollectOriginsHelper final : public Runnable {
+  uint64_t mMinSizeToBeFreed;
+
+  Mutex& mMutex;
+  CondVar mCondVar;
+
+  // The members below are protected by mMutex.
+  nsTArray<RefPtr<OriginDirectoryLock>> mLocks;
+  uint64_t mSizeToBeFreed;
+  bool mWaiting;
+
+ public:
+  CollectOriginsHelper(mozilla::Mutex& aMutex, uint64_t aMinSizeToBeFreed);
+
+  // Blocks the current thread until origins are collected on the main thread.
+  // The returned value contains an aggregate size of those origins.
+  int64_t BlockAndReturnOriginsForEviction(
+      nsTArray<RefPtr<OriginDirectoryLock>>& aLocks);
+
+ private:
+  ~CollectOriginsHelper() = default;
+
+  NS_IMETHOD
+  Run() override;
+};
+
+class OriginOperationBase : public BackgroundThreadObject, public Runnable {
+ protected:
+  nsresult mResultCode;
+
+  enum State {
+    // Not yet run.
+    State_Initial,
+
+    // Running on the owning thread in the listener for OpenDirectory.
+    State_DirectoryOpenPending,
+
+    // Running on the IO thread.
+    State_DirectoryWorkOpen,
+
+    // Running on the owning thread after all work is done.
+    State_UnblockingOpen,
+
+    // All done.
+    State_Complete
+  };
+
+ private:
+  State mState;
+  bool mActorDestroyed;
+
+ protected:
+  bool mNeedsQuotaManagerInit;
+  bool mNeedsStorageInit;
+
+ public:
+  void NoteActorDestroyed() {
+    AssertIsOnOwningThread();
+
+    mActorDestroyed = true;
+  }
+
+  bool IsActorDestroyed() const {
+    AssertIsOnOwningThread();
+
+    return mActorDestroyed;
+  }
+
+ protected:
+  explicit OriginOperationBase(nsISerialEventTarget* aOwningThread,
+                               const char* aRunnableName)
+      : BackgroundThreadObject(aOwningThread),
+        Runnable(aRunnableName),
+        mResultCode(NS_OK),
+        mState(State_Initial),
+        mActorDestroyed(false),
+        mNeedsQuotaManagerInit(false),
+        mNeedsStorageInit(false) {}
+
+  // Reference counted.
+  virtual ~OriginOperationBase() {
+    MOZ_ASSERT(mState == State_Complete);
+    MOZ_ASSERT(mActorDestroyed);
+  }
+
+#ifdef DEBUG
+  State GetState() const { return mState; }
+#endif
+
+  void SetState(State aState) {
+    MOZ_ASSERT(mState == State_Initial);
+    mState = aState;
+  }
+
+  void AdvanceState() {
+    switch (mState) {
+      case State_Initial:
+        mState = State_DirectoryOpenPending;
+        return;
+      case State_DirectoryOpenPending:
+        mState = State_DirectoryWorkOpen;
+        return;
+      case State_DirectoryWorkOpen:
+        mState = State_UnblockingOpen;
+        return;
+      case State_UnblockingOpen:
+        mState = State_Complete;
+        return;
+      default:
+        MOZ_CRASH("Bad state!");
+    }
+  }
+
+  NS_IMETHOD
+  Run() override;
+
+  virtual void Open() = 0;
+
+#ifdef DEBUG
+  virtual nsresult DirectoryOpen();
+#else
+  nsresult DirectoryOpen();
+#endif
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) = 0;
+
+  void Finish(nsresult aResult);
+
+  virtual void UnblockOpen() = 0;
+
+ private:
+  nsresult Init();
+
+  nsresult FinishInit();
+
+  nsresult DirectoryWork();
+};
+
+class FinalizeOriginEvictionOp : public OriginOperationBase {
+  nsTArray<RefPtr<OriginDirectoryLock>> mLocks;
+
+ public:
+  FinalizeOriginEvictionOp(nsISerialEventTarget* aBackgroundThread,
+                           nsTArray<RefPtr<OriginDirectoryLock>>&& aLocks)
+      : OriginOperationBase(aBackgroundThread,
+                            "dom::quota::FinalizeOriginEvictionOp"),
+        mLocks(std::move(aLocks)) {
+    MOZ_ASSERT(!NS_IsMainThread());
+  }
+
+  void Dispatch();
+
+  void RunOnIOThreadImmediately();
+
+ private:
+  ~FinalizeOriginEvictionOp() = default;
+
+  virtual void Open() override;
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  virtual void UnblockOpen() override;
+};
+
+class NormalOriginOperationBase
+    : public OriginOperationBase,
+      public OpenDirectoryListener,
+      public SupportsCheckedUnsafePtr<CheckIf<DiagnosticAssertEnabled>> {
+ protected:
+  OriginScope mOriginScope;
+  RefPtr<DirectoryLock> mDirectoryLock;
+  Nullable<PersistenceType> mPersistenceType;
+  Nullable<Client::Type> mClientType;
+  mozilla::Atomic<bool> mCanceled;
+  const bool mExclusive;
+
+ public:
+  void RunImmediately() {
+    MOZ_ASSERT(GetState() == State_Initial);
+
+    MOZ_ALWAYS_SUCCEEDS(this->Run());
+  }
+
+ protected:
+  NormalOriginOperationBase(const char* aRunnableName,
+                            const Nullable<PersistenceType>& aPersistenceType,
+                            const OriginScope& aOriginScope, bool aExclusive)
+      : OriginOperationBase(GetCurrentSerialEventTarget(), aRunnableName),
+        mOriginScope(aOriginScope),
+        mPersistenceType(aPersistenceType),
+        mExclusive(aExclusive) {
+    AssertIsOnOwningThread();
+  }
+
+  ~NormalOriginOperationBase() = default;
+
+  virtual RefPtr<DirectoryLock> CreateDirectoryLock();
+
+ private:
+  // Need to declare refcounting unconditionally, because
+  // OpenDirectoryListener has pure-virtual refcounting.
+  NS_DECL_ISUPPORTS_INHERITED
+
+  virtual void Open() override;
+
+  virtual void UnblockOpen() override;
+
+  // OpenDirectoryListener overrides.
+  virtual void DirectoryLockAcquired(DirectoryLock* aLock) override;
+
+  virtual void DirectoryLockFailed() override;
+
+  // Used to send results before unblocking open.
+  virtual void SendResults() = 0;
+};
+
+class SaveOriginAccessTimeOp : public NormalOriginOperationBase {
+  int64_t mTimestamp;
+
+ public:
+  SaveOriginAccessTimeOp(PersistenceType aPersistenceType,
+                         const nsACString& aOrigin, int64_t aTimestamp)
+      : NormalOriginOperationBase("dom::quota::SaveOriginAccessTimeOp",
+                                  Nullable<PersistenceType>(aPersistenceType),
+                                  OriginScope::FromOrigin(aOrigin),
+                                  /* aExclusive */ false),
+        mTimestamp(aTimestamp) {
+    AssertIsOnOwningThread();
+  }
+
+ private:
+  ~SaveOriginAccessTimeOp() = default;
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  virtual void SendResults() override;
+};
+
+class ShutdownStorageOp : public NormalOriginOperationBase {
+  MozPromiseHolder<BoolPromise> mPromiseHolder;
+
+ public:
+  ShutdownStorageOp()
+      : NormalOriginOperationBase("dom::quota::ShutdownStorageOp",
+                                  Nullable<PersistenceType>(),
+                                  OriginScope::FromNull(),
+                                  /* aExclusive */ true) {
+    AssertIsOnOwningThread();
+  }
+
+  RefPtr<BoolPromise> OnResults() {
+    AssertIsOnOwningThread();
+
+    return mPromiseHolder.Ensure(__func__);
+  }
+
+ private:
+  ~ShutdownStorageOp() = default;
+
+#ifdef DEBUG
+  nsresult DirectoryOpen() override;
+#endif
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void SendResults() override;
+};
+
+/*******************************************************************************
+ * Actor class declarations
+ ******************************************************************************/
+
+class Quota final : public PQuotaParent {
+#ifdef DEBUG
+  bool mActorDestroyed;
+#endif
+
+ public:
+  Quota();
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(mozilla::dom::quota::Quota)
+
+ private:
+  ~Quota();
+
+  bool VerifyRequestParams(const UsageRequestParams& aParams) const;
+
+  bool VerifyRequestParams(const RequestParams& aParams) const;
+
+  // IPDL methods.
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  virtual PQuotaUsageRequestParent* AllocPQuotaUsageRequestParent(
+      const UsageRequestParams& aParams) override;
+
+  virtual mozilla::ipc::IPCResult RecvPQuotaUsageRequestConstructor(
+      PQuotaUsageRequestParent* aActor,
+      const UsageRequestParams& aParams) override;
+
+  virtual bool DeallocPQuotaUsageRequestParent(
+      PQuotaUsageRequestParent* aActor) override;
+
+  virtual PQuotaRequestParent* AllocPQuotaRequestParent(
+      const RequestParams& aParams) override;
+
+  virtual mozilla::ipc::IPCResult RecvPQuotaRequestConstructor(
+      PQuotaRequestParent* aActor, const RequestParams& aParams) override;
+
+  virtual bool DeallocPQuotaRequestParent(PQuotaRequestParent* aActor) override;
+
+  virtual mozilla::ipc::IPCResult RecvStartIdleMaintenance() override;
+
+  virtual mozilla::ipc::IPCResult RecvStopIdleMaintenance() override;
+
+  virtual mozilla::ipc::IPCResult RecvAbortOperationsForProcess(
+      const ContentParentId& aContentParentId) override;
+};
+
+class QuotaUsageRequestBase : public NormalOriginOperationBase,
+                              public PQuotaUsageRequestParent {
+ public:
+  // May be overridden by subclasses if they need to perform work on the
+  // background thread before being run.
+  virtual void Init(Quota& aQuota);
+
+ protected:
+  QuotaUsageRequestBase(const char* aRunnableName)
+      : NormalOriginOperationBase(aRunnableName, Nullable<PersistenceType>(),
+                                  OriginScope::FromNull(),
+                                  /* aExclusive */ false) {}
+
+  mozilla::Result<UsageInfo, nsresult> GetUsageForOrigin(
+      QuotaManager& aQuotaManager, PersistenceType aPersistenceType,
+      const OriginMetadata& aOriginMetadata);
+
+  // Subclasses use this override to set the IPDL response value.
+  virtual void GetResponse(UsageRequestResponse& aResponse) = 0;
+
+ private:
+  mozilla::Result<UsageInfo, nsresult> GetUsageForOriginEntries(
+      QuotaManager& aQuotaManager, PersistenceType aPersistenceType,
+      const OriginMetadata& aOriginMetadata, nsIFile& aDirectory,
+      bool aInitialized);
+
+  void SendResults() override;
+
+  // IPDL methods.
+  void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  mozilla::ipc::IPCResult RecvCancel() final;
+};
+
+// A mix-in class to simplify operations that need to process every origin in
+// one or more repositories. Sub-classes should call TraverseRepository in their
+// DoDirectoryWork and implement a ProcessOrigin method for their per-origin
+// logic.
+class TraverseRepositoryHelper {
+ public:
+  TraverseRepositoryHelper() = default;
+
+ protected:
+  virtual ~TraverseRepositoryHelper() = default;
+
+  // If ProcessOrigin returns an error, TraverseRepository will immediately
+  // terminate and return the received error code to its caller.
+  nsresult TraverseRepository(QuotaManager& aQuotaManager,
+                              PersistenceType aPersistenceType);
+
+ private:
+  virtual const Atomic<bool>& GetIsCanceledFlag() = 0;
+
+  virtual nsresult ProcessOrigin(QuotaManager& aQuotaManager,
+                                 nsIFile& aOriginDir, const bool aPersistent,
+                                 const PersistenceType aPersistenceType) = 0;
+};
+
+class GetUsageOp final : public QuotaUsageRequestBase,
+                         public TraverseRepositoryHelper {
+  nsTArray<OriginUsage> mOriginUsages;
+  nsTHashMap<nsCStringHashKey, uint32_t> mOriginUsagesIndex;
+
+  bool mGetAll;
+
+ public:
+  explicit GetUsageOp(const UsageRequestParams& aParams);
+
+ private:
+  ~GetUsageOp() = default;
+
+  void ProcessOriginInternal(QuotaManager* aQuotaManager,
+                             const PersistenceType aPersistenceType,
+                             const nsACString& aOrigin,
+                             const int64_t aTimestamp, const bool aPersisted,
+                             const uint64_t aUsage);
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  const Atomic<bool>& GetIsCanceledFlag() override;
+
+  nsresult ProcessOrigin(QuotaManager& aQuotaManager, nsIFile& aOriginDir,
+                         const bool aPersistent,
+                         const PersistenceType aPersistenceType) override;
+
+  void GetResponse(UsageRequestResponse& aResponse) override;
+};
+
+class GetOriginUsageOp final : public QuotaUsageRequestBase {
+  nsCString mSuffix;
+  nsCString mGroup;
+  uint64_t mUsage;
+  uint64_t mFileUsage;
+  bool mFromMemory;
+
+ public:
+  explicit GetOriginUsageOp(const UsageRequestParams& aParams);
+
+ private:
+  ~GetOriginUsageOp() = default;
+
+  RefPtr<DirectoryLock> CreateDirectoryLock() override;
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(UsageRequestResponse& aResponse) override;
+};
+
+class QuotaRequestBase : public NormalOriginOperationBase,
+                         public PQuotaRequestParent {
+ public:
+  // May be overridden by subclasses if they need to perform work on the
+  // background thread before being run.
+  virtual void Init(Quota& aQuota);
+
+ protected:
+  explicit QuotaRequestBase(const char* aRunnableName, bool aExclusive)
+      : NormalOriginOperationBase(aRunnableName, Nullable<PersistenceType>(),
+                                  OriginScope::FromNull(), aExclusive) {}
+
+  // Subclasses use this override to set the IPDL response value.
+  virtual void GetResponse(RequestResponse& aResponse) = 0;
+
+ private:
+  virtual void SendResults() override;
+
+  // IPDL methods.
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+};
+
+class StorageNameOp final : public QuotaRequestBase {
+  nsString mName;
+
+ public:
+  StorageNameOp();
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~StorageNameOp() = default;
+
+  RefPtr<DirectoryLock> CreateDirectoryLock() override;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class InitializedRequestBase : public QuotaRequestBase {
+ protected:
+  bool mInitialized;
+
+ public:
+  void Init(Quota& aQuota) override;
+
+ protected:
+  InitializedRequestBase(const char* aRunnableName);
+
+ private:
+  RefPtr<DirectoryLock> CreateDirectoryLock() override;
+};
+
+class StorageInitializedOp final : public InitializedRequestBase {
+ public:
+  StorageInitializedOp()
+      : InitializedRequestBase("dom::quota::StorageInitializedOp") {}
+
+ private:
+  ~StorageInitializedOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class TemporaryStorageInitializedOp final : public InitializedRequestBase {
+ public:
+  TemporaryStorageInitializedOp()
+      : InitializedRequestBase("dom::quota::StorageInitializedOp") {}
+
+ private:
+  ~TemporaryStorageInitializedOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class InitOp final : public QuotaRequestBase {
+ public:
+  InitOp();
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~InitOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class InitTemporaryStorageOp final : public QuotaRequestBase {
+ public:
+  InitTemporaryStorageOp();
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~InitTemporaryStorageOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class InitializeOriginRequestBase : public QuotaRequestBase {
+ protected:
+  nsCString mSuffix;
+  nsCString mGroup;
+  bool mCreated;
+
+ public:
+  void Init(Quota& aQuota) override;
+
+ protected:
+  InitializeOriginRequestBase(const char* aRunnableName,
+                              PersistenceType aPersistenceType,
+                              const PrincipalInfo& aPrincipalInfo);
+};
+
+class InitializePersistentOriginOp final : public InitializeOriginRequestBase {
+ public:
+  explicit InitializePersistentOriginOp(const RequestParams& aParams);
+
+ private:
+  ~InitializePersistentOriginOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class InitializeTemporaryOriginOp final : public InitializeOriginRequestBase {
+ public:
+  explicit InitializeTemporaryOriginOp(const RequestParams& aParams);
+
+ private:
+  ~InitializeTemporaryOriginOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class GetFullOriginMetadataOp : public QuotaRequestBase {
+  const OriginMetadata mOriginMetadata;
+  Maybe<FullOriginMetadata> mMaybeFullOriginMetadata;
+
+ public:
+  explicit GetFullOriginMetadataOp(const GetFullOriginMetadataParams& aParams);
+
+ private:
+  RefPtr<DirectoryLock> CreateDirectoryLock() override;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class ResetOrClearOp final : public QuotaRequestBase {
+  const bool mClear;
+
+ public:
+  explicit ResetOrClearOp(bool aClear);
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~ResetOrClearOp() = default;
+
+  void DeleteFiles(QuotaManager& aQuotaManager);
+
+  void DeleteStorageFile(QuotaManager& aQuotaManager);
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  virtual void GetResponse(RequestResponse& aResponse) override;
+};
+
+class ClearRequestBase : public QuotaRequestBase {
+ protected:
+  explicit ClearRequestBase(const char* aRunnableName, bool aExclusive)
+      : QuotaRequestBase(aRunnableName, aExclusive) {
+    AssertIsOnOwningThread();
+  }
+
+  void DeleteFiles(QuotaManager& aQuotaManager,
+                   PersistenceType aPersistenceType);
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+};
+
+class ClearOriginOp final : public ClearRequestBase {
+  const ClearResetOriginParams mParams;
+  const bool mMatchAll;
+
+ public:
+  explicit ClearOriginOp(const RequestParams& aParams);
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~ClearOriginOp() = default;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class ClearDataOp final : public ClearRequestBase {
+  const ClearDataParams mParams;
+
+ public:
+  explicit ClearDataOp(const RequestParams& aParams);
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~ClearDataOp() = default;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class ResetOriginOp final : public QuotaRequestBase {
+ public:
+  explicit ResetOriginOp(const RequestParams& aParams);
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~ResetOriginOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class PersistRequestBase : public QuotaRequestBase {
+  const PrincipalInfo mPrincipalInfo;
+
+ protected:
+  nsCString mSuffix;
+  nsCString mGroup;
+
+ public:
+  void Init(Quota& aQuota) override;
+
+ protected:
+  explicit PersistRequestBase(const PrincipalInfo& aPrincipalInfo);
+};
+
+class PersistedOp final : public PersistRequestBase {
+  bool mPersisted;
+
+ public:
+  explicit PersistedOp(const RequestParams& aParams);
+
+ private:
+  ~PersistedOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class PersistOp final : public PersistRequestBase {
+ public:
+  explicit PersistOp(const RequestParams& aParams);
+
+ private:
+  ~PersistOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class EstimateOp final : public QuotaRequestBase {
+  const OriginMetadata mOriginMetadata;
+  std::pair<uint64_t, uint64_t> mUsageAndLimit;
+
+ public:
+  explicit EstimateOp(const EstimateParams& aParams);
+
+ private:
+  ~EstimateOp() = default;
+
+  RefPtr<DirectoryLock> CreateDirectoryLock() override;
+
+  virtual nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+class ListOriginsOp final : public QuotaRequestBase,
+                            public TraverseRepositoryHelper {
+  // XXX Bug 1521541 will make each origin has it's own state.
+  nsTArray<nsCString> mOrigins;
+
+ public:
+  ListOriginsOp();
+
+  void Init(Quota& aQuota) override;
+
+ private:
+  ~ListOriginsOp() = default;
+
+  nsresult DoDirectoryWork(QuotaManager& aQuotaManager) override;
+
+  const Atomic<bool>& GetIsCanceledFlag() override;
+
+  nsresult ProcessOrigin(QuotaManager& aQuotaManager, nsIFile& aOriginDir,
+                         const bool aPersistent,
+                         const PersistenceType aPersistenceType) override;
+
+  void GetResponse(RequestResponse& aResponse) override;
+};
+
+/*******************************************************************************
+ * Other class declarations
+ ******************************************************************************/
+
+class StoragePressureRunnable final : public Runnable {
+  const uint64_t mUsage;
+
+ public:
+  explicit StoragePressureRunnable(uint64_t aUsage)
+      : Runnable("dom::quota::QuotaObject::StoragePressureRunnable"),
+        mUsage(aUsage) {}
+
+ private:
+  ~StoragePressureRunnable() = default;
+
+  NS_DECL_NSIRUNNABLE
+};
+
+class RecordQuotaInfoLoadTimeHelper final : public Runnable {
+  // TimeStamps that are set on the IO thread.
+  LazyInitializedOnceNotNull<const TimeStamp> mStartTime;
+  LazyInitializedOnceNotNull<const TimeStamp> mEndTime;
+
+  // A TimeStamp that is set on the main thread.
+  LazyInitializedOnceNotNull<const TimeStamp> mInitializedTime;
+
+ public:
+  RecordQuotaInfoLoadTimeHelper()
+      : Runnable("dom::quota::RecordQuotaInfoLoadTimeHelper") {}
+
+  TimeStamp Start();
+
+  TimeStamp End();
+
+ private:
+  ~RecordQuotaInfoLoadTimeHelper() = default;
+
+  NS_DECL_NSIRUNNABLE
+};
+
+/*******************************************************************************
+ * Helper classes
+ ******************************************************************************/
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+
+class PrincipalVerifier final : public Runnable {
+  nsTArray<PrincipalInfo> mPrincipalInfos;
+
+ public:
+  static already_AddRefed<PrincipalVerifier> CreateAndDispatch(
+      nsTArray<PrincipalInfo>&& aPrincipalInfos);
+
+ private:
+  explicit PrincipalVerifier(nsTArray<PrincipalInfo>&& aPrincipalInfos)
+      : Runnable("dom::quota::PrincipalVerifier"),
+        mPrincipalInfos(std::move(aPrincipalInfos)) {
+    AssertIsOnIOThread();
+  }
+
+  virtual ~PrincipalVerifier() = default;
+
+  Result<Ok, nsCString> CheckPrincipalInfoValidity(
+      const PrincipalInfo& aPrincipalInfo);
+
+  NS_DECL_NSIRUNNABLE
+};
+
+#endif
+
+/*******************************************************************************
+ * Helper Functions
+ ******************************************************************************/
+
+inline bool IsDotFile(const nsAString& aFileName) {
+  return QuotaManager::IsDotFile(aFileName);
+}
+
+inline bool IsOSMetadata(const nsAString& aFileName) {
+  return QuotaManager::IsOSMetadata(aFileName);
+}
+
+bool IsOriginMetadata(const nsAString& aFileName) {
+  return aFileName.EqualsLiteral(METADATA_FILE_NAME) ||
+         aFileName.EqualsLiteral(METADATA_V2_FILE_NAME) ||
+         IsOSMetadata(aFileName);
+}
+
+bool IsTempMetadata(const nsAString& aFileName) {
+  return aFileName.EqualsLiteral(METADATA_TMP_FILE_NAME) ||
+         aFileName.EqualsLiteral(METADATA_V2_TMP_FILE_NAME);
+}
+
+// Return whether the group was actually updated.
+Result<bool, nsresult> MaybeUpdateGroupForOrigin(
+    OriginMetadata& aOriginMetadata) {
+  MOZ_ASSERT(!NS_IsMainThread());
+
+  bool updated = false;
+
+  if (aOriginMetadata.mOrigin.EqualsLiteral(kChromeOrigin)) {
+    if (!aOriginMetadata.mGroup.EqualsLiteral(kChromeOrigin)) {
+      aOriginMetadata.mGroup.AssignLiteral(kChromeOrigin);
+      updated = true;
+    }
+  } else {
+    OriginAttributes originAttributes;
+    nsCString originNoSuffix;
+    QM_TRY(OkIf(originAttributes.PopulateFromOrigin(aOriginMetadata.mOrigin,
+                                                    originNoSuffix)),
+           Err(NS_ERROR_FAILURE));
+
+    RefPtr<MozURL> url;
+    QM_TRY(MOZ_TO_RESULT(MozURL::Init(getter_AddRefs(url), originNoSuffix)),
+           QM_PROPAGATE, [&originNoSuffix](const nsresult) {
+             QM_WARNING("A URL %s is not recognized by MozURL",
+                        originNoSuffix.get());
+           });
+
+    QM_TRY_INSPECT(
+        const auto& baseDomain,
+        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoCString, *url, BaseDomain));
+
+    const nsCString upToDateGroup = baseDomain + aOriginMetadata.mSuffix;
+
+    if (aOriginMetadata.mGroup != upToDateGroup) {
+      aOriginMetadata.mGroup = upToDateGroup;
+      updated = true;
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+      ContentPrincipalInfo contentPrincipalInfo;
+      contentPrincipalInfo.attrs() = originAttributes;
+      contentPrincipalInfo.originNoSuffix() = originNoSuffix;
+      contentPrincipalInfo.spec() = originNoSuffix;
+      contentPrincipalInfo.baseDomain() = baseDomain;
+
+      PrincipalInfo principalInfo(contentPrincipalInfo);
+
+      nsTArray<PrincipalInfo> principalInfos;
+      principalInfos.AppendElement(principalInfo);
+
+      RefPtr<PrincipalVerifier> principalVerifier =
+          PrincipalVerifier::CreateAndDispatch(std::move(principalInfos));
+#endif
+    }
+  }
+
+  return updated;
+}
+
+Result<bool, nsresult> MaybeUpdateLastAccessTimeForOrigin(
+    FullOriginMetadata& aFullOriginMetadata) {
+  MOZ_ASSERT(!NS_IsMainThread());
+
+  if (aFullOriginMetadata.mLastAccessTime == INT64_MIN) {
+    QuotaManager* quotaManager = QuotaManager::Get();
+    MOZ_ASSERT(quotaManager);
+
+    QM_TRY_INSPECT(
+        const auto& metadataFile,
+        quotaManager->GetDirectoryForOrigin(
+            aFullOriginMetadata.mPersistenceType, aFullOriginMetadata.mOrigin));
+
+    QM_TRY(MOZ_TO_RESULT(
+        metadataFile->Append(nsLiteralString(METADATA_V2_FILE_NAME))));
+
+    QM_TRY_UNWRAP(int64_t timestamp, MOZ_TO_RESULT_INVOKE_MEMBER(
+                                         metadataFile, GetLastModifiedTime));
+
+    // Need to convert from milliseconds to microseconds.
+    MOZ_ASSERT((INT64_MAX / PR_USEC_PER_MSEC) > timestamp);
+    timestamp *= int64_t(PR_USEC_PER_MSEC);
+
+    aFullOriginMetadata.mLastAccessTime = timestamp;
+
+    return true;
+  }
+
+  return false;
+}
+
+}  // namespace
+
+BackgroundThreadObject::BackgroundThreadObject()
+    : mOwningThread(GetCurrentSerialEventTarget()) {
+  AssertIsOnOwningThread();
+}
+
+BackgroundThreadObject::BackgroundThreadObject(
+    nsISerialEventTarget* aOwningThread)
+    : mOwningThread(aOwningThread) {}
+
+#ifdef DEBUG
+
+void BackgroundThreadObject::AssertIsOnOwningThread() const {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(mOwningThread);
+  bool current;
+  MOZ_ASSERT(NS_SUCCEEDED(mOwningThread->IsOnCurrentThread(&current)));
+  MOZ_ASSERT(current);
+}
+
+#endif  // DEBUG
+
+nsISerialEventTarget* BackgroundThreadObject::OwningThread() const {
+  MOZ_ASSERT(mOwningThread);
+  return mOwningThread;
+}
+
+bool IsOnIOThread() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  NS_ASSERTION(quotaManager, "Must have a manager here!");
+
+  bool currentThread;
+  return NS_SUCCEEDED(
+             quotaManager->IOThread()->IsOnCurrentThread(&currentThread)) &&
+         currentThread;
+}
+
+void AssertIsOnIOThread() {
+  NS_ASSERTION(IsOnIOThread(), "Running on the wrong thread!");
+}
+
+void DiagnosticAssertIsOnIOThread() { MOZ_DIAGNOSTIC_ASSERT(IsOnIOThread()); }
+
+void AssertCurrentThreadOwnsQuotaMutex() {
+#ifdef DEBUG
+  QuotaManager* quotaManager = QuotaManager::Get();
+  NS_ASSERTION(quotaManager, "Must have a manager here!");
+
+  quotaManager->AssertCurrentThreadOwnsQuotaMutex();
+#endif
+}
+
+void ReportInternalError(const char* aFile, uint32_t aLine, const char* aStr) {
+  // Get leaf of file path
+  for (const char* p = aFile; *p; ++p) {
+    if (*p == '/' && *(p + 1)) {
+      aFile = p + 1;
+    }
+  }
+
+  nsContentUtils::LogSimpleConsoleError(
+      NS_ConvertUTF8toUTF16(
+          nsPrintfCString("Quota %s: %s:%" PRIu32, aStr, aFile, aLine)),
+      "quota"_ns,
+      false /* Quota Manager is not active in private browsing mode */,
+      true /* Quota Manager runs always in a chrome context */);
+}
+
+namespace {
+
+bool gInvalidateQuotaCache = false;
+StaticAutoPtr<nsString> gBasePath;
+StaticAutoPtr<nsString> gStorageName;
+StaticAutoPtr<nsCString> gBuildId;
+
+#ifdef DEBUG
+bool gQuotaManagerInitialized = false;
+#endif
+
+StaticRefPtr<QuotaManager> gInstance;
+mozilla::Atomic<bool> gShutdown(false);
+
+// A time stamp that can only be accessed on the main thread.
+TimeStamp gLastOSWake;
+
+using NormalOriginOpArray =
+    nsTArray<CheckedUnsafePtr<NormalOriginOperationBase>>;
+StaticAutoPtr<NormalOriginOpArray> gNormalOriginOps;
+
+void RegisterNormalOriginOp(NormalOriginOperationBase& aNormalOriginOp) {
+  AssertIsOnBackgroundThread();
+
+  if (!gNormalOriginOps) {
+    gNormalOriginOps = new NormalOriginOpArray();
+  }
+
+  gNormalOriginOps->AppendElement(&aNormalOriginOp);
+}
+
+void UnregisterNormalOriginOp(NormalOriginOperationBase& aNormalOriginOp) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(gNormalOriginOps);
+
+  gNormalOriginOps->RemoveElement(&aNormalOriginOp);
+
+  if (gNormalOriginOps->IsEmpty()) {
+    gNormalOriginOps = nullptr;
+  }
+}
+
+class StorageOperationBase {
+ protected:
+  struct OriginProps {
+    enum Type { eChrome, eContent, eObsolete, eInvalid };
+
+    NotNull<nsCOMPtr<nsIFile>> mDirectory;
+    nsString mLeafName;
+    nsCString mSpec;
+    OriginAttributes mAttrs;
+    int64_t mTimestamp;
+    OriginMetadata mOriginMetadata;
+    nsCString mOriginalSuffix;
+
+    LazyInitializedOnceEarlyDestructible<const PersistenceType>
+        mPersistenceType;
+    Type mType;
+    bool mNeedsRestore;
+    bool mNeedsRestore2;
+    bool mIgnore;
+
+   public:
+    explicit OriginProps(MovingNotNull<nsCOMPtr<nsIFile>> aDirectory)
+        : mDirectory(std::move(aDirectory)),
+          mTimestamp(0),
+          mType(eContent),
+          mNeedsRestore(false),
+          mNeedsRestore2(false),
+          mIgnore(false) {}
+
+    template <typename PersistenceTypeFunc>
+    nsresult Init(PersistenceTypeFunc&& aPersistenceTypeFunc);
+  };
+
+  nsTArray<OriginProps> mOriginProps;
+
+  nsCOMPtr<nsIFile> mDirectory;
+
+ public:
+  explicit StorageOperationBase(nsIFile* aDirectory) : mDirectory(aDirectory) {
+    AssertIsOnIOThread();
+  }
+
+  NS_INLINE_DECL_REFCOUNTING(StorageOperationBase)
+
+ protected:
+  virtual ~StorageOperationBase() = default;
+
+  nsresult GetDirectoryMetadata(nsIFile* aDirectory, int64_t& aTimestamp,
+                                nsACString& aGroup, nsACString& aOrigin,
+                                Nullable<bool>& aIsApp);
+
+  // Upgrade helper to load the contents of ".metadata-v2" files from previous
+  // schema versions.  Although QuotaManager has a similar GetDirectoryMetadata2
+  // method, it is only intended to read current version ".metadata-v2" files.
+  // And unlike the old ".metadata" files, the ".metadata-v2" format can evolve
+  // because our "storage.sqlite" lets us track the overall version of the
+  // storage directory.
+  nsresult GetDirectoryMetadata2(nsIFile* aDirectory, int64_t& aTimestamp,
+                                 nsACString& aSuffix, nsACString& aGroup,
+                                 nsACString& aOrigin, bool& aIsApp);
+
+  int64_t GetOriginLastModifiedTime(const OriginProps& aOriginProps);
+
+  nsresult RemoveObsoleteOrigin(const OriginProps& aOriginProps);
+
+  /**
+   * Rename the origin if the origin string generation from nsIPrincipal
+   * changed. This consists of renaming the origin in the metadata files and
+   * renaming the origin directory itself. For simplicity, the origin in
+   * metadata files is not actually updated, but the metadata files are
+   * recreated instead.
+   *
+   * @param  aOriginProps the properties of the origin to check.
+   *
+   * @return whether origin was renamed.
+   */
+  Result<bool, nsresult> MaybeRenameOrigin(const OriginProps& aOriginProps);
+
+  nsresult ProcessOriginDirectories();
+
+  virtual nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) = 0;
+};
+
+class MOZ_STACK_CLASS OriginParser final {
+ public:
+  enum ResultType { InvalidOrigin, ObsoleteOrigin, ValidOrigin };
+
+ private:
+  using Tokenizer =
+      nsCCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing>;
+
+  enum SchemeType { eNone, eFile, eAbout, eChrome };
+
+  enum State {
+    eExpectingAppIdOrScheme,
+    eExpectingInMozBrowser,
+    eExpectingScheme,
+    eExpectingEmptyToken1,
+    eExpectingEmptyToken2,
+    eExpectingEmptyTokenOrUniversalFileOrigin,
+    eExpectingHost,
+    eExpectingPort,
+    eExpectingEmptyTokenOrDriveLetterOrPathnameComponent,
+    eExpectingEmptyTokenOrPathnameComponent,
+    eExpectingEmptyToken1OrHost,
+
+    // We transit from eExpectingHost to this state when we encounter a host
+    // beginning with "[" which indicates an IPv6 literal. Because we mangle the
+    // IPv6 ":" delimiter to be a "+", we will receive separate tokens for each
+    // portion of the IPv6 address, including a final token that ends with "]".
+    // (Note that we do not mangle "[" or "]".) Note that the URL spec
+    // explicitly disclaims support for "<zone_id>" and so we don't have to deal
+    // with that.
+    eExpectingIPV6Token,
+    eComplete,
+    eHandledTrailingSeparator
+  };
+
+  const nsCString mOrigin;
+  Tokenizer mTokenizer;
+
+  nsCString mScheme;
+  nsCString mHost;
+  Nullable<uint32_t> mPort;
+  nsTArray<nsCString> mPathnameComponents;
+  nsCString mHandledTokens;
+
+  SchemeType mSchemeType;
+  State mState;
+  bool mInIsolatedMozBrowser;
+  bool mUniversalFileOrigin;
+  bool mMaybeDriveLetter;
+  bool mError;
+  bool mMaybeObsolete;
+
+  // Number of group which a IPv6 address has. Should be less than 9.
+  uint8_t mIPGroup;
+
+ public:
+  explicit OriginParser(const nsACString& aOrigin)
+      : mOrigin(aOrigin),
+        mTokenizer(aOrigin, '+'),
+        mPort(),
+        mSchemeType(eNone),
+        mState(eExpectingAppIdOrScheme),
+        mInIsolatedMozBrowser(false),
+        mUniversalFileOrigin(false),
+        mMaybeDriveLetter(false),
+        mError(false),
+        mMaybeObsolete(false),
+        mIPGroup(0) {}
+
+  static ResultType ParseOrigin(const nsACString& aOrigin, nsCString& aSpec,
+                                OriginAttributes* aAttrs,
+                                nsCString& aOriginalSuffix);
+
+  ResultType Parse(nsACString& aSpec);
+
+ private:
+  void HandleScheme(const nsDependentCSubstring& aToken);
+
+  void HandlePathnameComponent(const nsDependentCSubstring& aToken);
+
+  void HandleToken(const nsDependentCSubstring& aToken);
+
+  void HandleTrailingSeparator();
+};
+
+class RepositoryOperationBase : public StorageOperationBase {
+ public:
+  explicit RepositoryOperationBase(nsIFile* aDirectory)
+      : StorageOperationBase(aDirectory) {}
+
+  nsresult ProcessRepository();
+
+ protected:
+  virtual ~RepositoryOperationBase() = default;
+
+  template <typename UpgradeMethod>
+  nsresult MaybeUpgradeClients(const OriginProps& aOriginsProps,
+                               UpgradeMethod aMethod);
+
+ private:
+  virtual PersistenceType PersistenceTypeFromSpec(const nsCString& aSpec) = 0;
+
+  virtual nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                          bool* aRemoved) = 0;
+
+  virtual nsresult PrepareClientDirectory(nsIFile* aFile,
+                                          const nsAString& aLeafName,
+                                          bool& aRemoved);
+};
+
+class CreateOrUpgradeDirectoryMetadataHelper final
+    : public RepositoryOperationBase {
+  nsCOMPtr<nsIFile> mPermanentStorageDir;
+
+  // The legacy PersistenceType, before the default repository introduction.
+  enum class LegacyPersistenceType {
+    Persistent = 0,
+    Temporary
+    // The PersistenceType had also PERSISTENCE_TYPE_INVALID, but we don't need
+    // it here.
+  };
+
+  LazyInitializedOnce<const LegacyPersistenceType> mLegacyPersistenceType;
+
+ public:
+  explicit CreateOrUpgradeDirectoryMetadataHelper(nsIFile* aDirectory)
+      : RepositoryOperationBase(aDirectory) {}
+
+  nsresult Init();
+
+ private:
+  Maybe<LegacyPersistenceType> LegacyPersistenceTypeFromFile(nsIFile& aFile,
+                                                             const fallible_t&);
+
+  PersistenceType PersistenceTypeFromLegacyPersistentSpec(
+      const nsCString& aSpec);
+
+  PersistenceType PersistenceTypeFromSpec(const nsCString& aSpec) override;
+
+  nsresult MaybeUpgradeOriginDirectory(nsIFile* aDirectory);
+
+  nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                  bool* aRemoved) override;
+
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+};
+
+class UpgradeStorageHelperBase : public RepositoryOperationBase {
+  LazyInitializedOnce<const PersistenceType> mPersistenceType;
+
+ public:
+  explicit UpgradeStorageHelperBase(nsIFile* aDirectory)
+      : RepositoryOperationBase(aDirectory) {}
+
+  nsresult Init();
+
+ private:
+  PersistenceType PersistenceTypeFromSpec(const nsCString& aSpec) override;
+};
+
+class UpgradeStorageFrom0_0To1_0Helper final : public UpgradeStorageHelperBase {
+ public:
+  explicit UpgradeStorageFrom0_0To1_0Helper(nsIFile* aDirectory)
+      : UpgradeStorageHelperBase(aDirectory) {}
+
+ private:
+  nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                  bool* aRemoved) override;
+
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+};
+
+class UpgradeStorageFrom1_0To2_0Helper final : public UpgradeStorageHelperBase {
+ public:
+  explicit UpgradeStorageFrom1_0To2_0Helper(nsIFile* aDirectory)
+      : UpgradeStorageHelperBase(aDirectory) {}
+
+ private:
+  nsresult MaybeRemoveMorgueDirectory(const OriginProps& aOriginProps);
+
+  /**
+   * Remove the origin directory if appId is present in origin attributes.
+   *
+   * @param aOriginProps the properties of the origin to check.
+   *
+   * @return whether the origin directory was removed.
+   */
+  Result<bool, nsresult> MaybeRemoveAppsData(const OriginProps& aOriginProps);
+
+  nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                  bool* aRemoved) override;
+
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+};
+
+class UpgradeStorageFrom2_0To2_1Helper final : public UpgradeStorageHelperBase {
+ public:
+  explicit UpgradeStorageFrom2_0To2_1Helper(nsIFile* aDirectory)
+      : UpgradeStorageHelperBase(aDirectory) {}
+
+ private:
+  nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                  bool* aRemoved) override;
+
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+};
+
+class UpgradeStorageFrom2_1To2_2Helper final : public UpgradeStorageHelperBase {
+ public:
+  explicit UpgradeStorageFrom2_1To2_2Helper(nsIFile* aDirectory)
+      : UpgradeStorageHelperBase(aDirectory) {}
+
+ private:
+  nsresult PrepareOriginDirectory(OriginProps& aOriginProps,
+                                  bool* aRemoved) override;
+
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+
+  nsresult PrepareClientDirectory(nsIFile* aFile, const nsAString& aLeafName,
+                                  bool& aRemoved) override;
+};
+
+class RestoreDirectoryMetadata2Helper final : public StorageOperationBase {
+  LazyInitializedOnce<const PersistenceType> mPersistenceType;
+
+ public:
+  explicit RestoreDirectoryMetadata2Helper(nsIFile* aDirectory)
+      : StorageOperationBase(aDirectory) {}
+
+  nsresult Init();
+
+  nsresult RestoreMetadata2File();
+
+ private:
+  nsresult ProcessOriginDirectory(const OriginProps& aOriginProps) override;
+};
+
+auto MakeSanitizedOriginCString(const nsACString& aOrigin) {
+#ifdef XP_WIN
+  NS_ASSERTION(!strcmp(QuotaManager::kReplaceChars,
+                       FILE_ILLEGAL_CHARACTERS FILE_PATH_SEPARATOR),
+               "Illegal file characters have changed!");
+#endif
+
+  nsAutoCString res{aOrigin};
+
+  res.ReplaceChar(QuotaManager::kReplaceChars, '+');
+
+  return res;
+}
+
+auto MakeSanitizedOriginString(const nsACString& aOrigin) {
+  // An origin string is ASCII-only, since it is obtained via
+  // nsIPrincipal::GetOrigin, which returns an ACString.
+  return NS_ConvertASCIItoUTF16(MakeSanitizedOriginCString(aOrigin));
+}
+
+Result<nsAutoString, nsresult> GetPathForStorage(
+    nsIFile& aBaseDir, const nsAString& aStorageName) {
+  QM_TRY_INSPECT(const auto& storageDir,
+                 CloneFileAndAppend(aBaseDir, aStorageName));
+
+  QM_TRY_RETURN(
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, storageDir, GetPath));
+}
+
+int64_t GetLastModifiedTime(PersistenceType aPersistenceType, nsIFile& aFile) {
+  AssertIsOnIOThread();
+
+  class MOZ_STACK_CLASS Helper final {
+   public:
+    static nsresult GetLastModifiedTime(nsIFile* aFile, int64_t* aTimestamp) {
+      AssertIsOnIOThread();
+      MOZ_ASSERT(aFile);
+      MOZ_ASSERT(aTimestamp);
+
+      QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*aFile));
+
+      switch (dirEntryKind) {
+        case nsIFileKind::ExistsAsDirectory:
+          QM_TRY(CollectEachFile(
+              *aFile,
+              [&aTimestamp](const nsCOMPtr<nsIFile>& file)
+                  -> Result<mozilla::Ok, nsresult> {
+                QM_TRY(MOZ_TO_RESULT(GetLastModifiedTime(file, aTimestamp)));
+
+                return Ok{};
+              }));
+          break;
+
+        case nsIFileKind::ExistsAsFile: {
+          QM_TRY_INSPECT(const auto& leafName,
+                         MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, aFile,
+                                                           GetLeafName));
+
+          // Bug 1595445 will handle unknown files here.
+
+          if (IsOriginMetadata(leafName) || IsTempMetadata(leafName) ||
+              IsDotFile(leafName)) {
+            return NS_OK;
+          }
+
+          QM_TRY_UNWRAP(int64_t timestamp, MOZ_TO_RESULT_INVOKE_MEMBER(
+                                               aFile, GetLastModifiedTime));
+
+          // Need to convert from milliseconds to microseconds.
+          MOZ_ASSERT((INT64_MAX / PR_USEC_PER_MSEC) > timestamp);
+          timestamp *= int64_t(PR_USEC_PER_MSEC);
+
+          if (timestamp > *aTimestamp) {
+            *aTimestamp = timestamp;
+          }
+          break;
+        }
+
+        case nsIFileKind::DoesNotExist:
+          // Ignore files that got removed externally while iterating.
+          break;
+      }
+
+      return NS_OK;
+    }
+  };
+
+  if (aPersistenceType == PERSISTENCE_TYPE_PERSISTENT) {
+    return PR_Now();
+  }
+
+  int64_t timestamp = INT64_MIN;
+  nsresult rv = Helper::GetLastModifiedTime(&aFile, &timestamp);
+  if (NS_FAILED(rv)) {
+    timestamp = PR_Now();
+  }
+
+  // XXX if there were no suitable files for getting last modified time
+  // (timestamp is still set to INT64_MIN), we should return the current time
+  // instead of returning INT64_MIN.
+
+  return timestamp;
+}
+
+// Returns a bool indicating whether the directory was newly created.
+Result<bool, nsresult> EnsureDirectory(nsIFile& aDirectory) {
+  AssertIsOnIOThread();
+
+  // Callers call this function without checking if the directory already
+  // exists (idempotent usage). QM_OR_ELSE_WARN_IF is not used here since we
+  // just want to log NS_ERROR_FILE_ALREADY_EXISTS result and not spam the
+  // reports.
+  QM_TRY_INSPECT(const auto& exists,
+                 QM_OR_ELSE_LOG_VERBOSE_IF(
+                     // Expression.
+                     MOZ_TO_RESULT_INVOKE_MEMBER(aDirectory, Create,
+                                                 nsIFile::DIRECTORY_TYPE, 0755,
+                                                 /* aSkipAncestors = */ false)
+                         .map([](Ok) { return false; }),
+                     // Predicate.
+                     IsSpecificError<NS_ERROR_FILE_ALREADY_EXISTS>,
+                     // Fallback.
+                     ErrToOk<true>));
+
+  if (exists) {
+    QM_TRY_INSPECT(const bool& isDirectory,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aDirectory, IsDirectory));
+    QM_TRY(OkIf(isDirectory), Err(NS_ERROR_UNEXPECTED));
+  }
+
+  return !exists;
+}
+
+enum FileFlag { Truncate, Update, Append };
+
+Result<nsCOMPtr<nsIOutputStream>, nsresult> GetOutputStream(
+    nsIFile& aFile, FileFlag aFileFlag) {
+  AssertIsOnIOThread();
+
+  switch (aFileFlag) {
+    case FileFlag::Truncate:
+      QM_TRY_RETURN(NS_NewLocalFileOutputStream(&aFile));
+
+    case FileFlag::Update: {
+      QM_TRY_INSPECT(const bool& exists,
+                     MOZ_TO_RESULT_INVOKE_MEMBER(&aFile, Exists));
+
+      if (!exists) {
+        return nsCOMPtr<nsIOutputStream>();
+      }
+
+      QM_TRY_INSPECT(const auto& stream,
+                     NS_NewLocalFileRandomAccessStream(&aFile));
+
+      nsCOMPtr<nsIOutputStream> outputStream = do_QueryInterface(stream);
+      QM_TRY(OkIf(outputStream), Err(NS_ERROR_FAILURE));
+
+      return outputStream;
+    }
+
+    case FileFlag::Append:
+      QM_TRY_RETURN(NS_NewLocalFileOutputStream(
+          &aFile, PR_WRONLY | PR_CREATE_FILE | PR_APPEND));
+
+    default:
+      MOZ_CRASH("Should never get here!");
+  }
+}
+
+Result<nsCOMPtr<nsIBinaryOutputStream>, nsresult> GetBinaryOutputStream(
+    nsIFile& aFile, FileFlag aFileFlag) {
+  QM_TRY_UNWRAP(auto outputStream, GetOutputStream(aFile, aFileFlag));
+
+  QM_TRY(OkIf(outputStream), Err(NS_ERROR_UNEXPECTED));
+
+  return nsCOMPtr<nsIBinaryOutputStream>(
+      NS_NewObjectOutputStream(outputStream));
+}
+
+void GetJarPrefix(bool aInIsolatedMozBrowser, nsACString& aJarPrefix) {
+  aJarPrefix.Truncate();
+
+  // Fallback.
+  if (!aInIsolatedMozBrowser) {
+    return;
+  }
+
+  // AppId is an unused b2g identifier. Let's set it to 0 all the time (see bug
+  // 1320404).
+  // aJarPrefix = appId + "+" + { 't', 'f' } + "+";
+  aJarPrefix.AppendInt(0);  // TODO: this is the appId, to be removed.
+  aJarPrefix.Append('+');
+  aJarPrefix.Append(aInIsolatedMozBrowser ? 't' : 'f');
+  aJarPrefix.Append('+');
+}
+
+nsresult CreateDirectoryMetadata(nsIFile& aDirectory, int64_t aTimestamp,
+                                 const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  OriginAttributes groupAttributes;
+
+  nsCString groupNoSuffix;
+  QM_TRY(OkIf(groupAttributes.PopulateFromOrigin(aOriginMetadata.mGroup,
+                                                 groupNoSuffix)),
+         NS_ERROR_FAILURE);
+
+  nsCString groupPrefix;
+  GetJarPrefix(groupAttributes.mInIsolatedMozBrowser, groupPrefix);
+
+  nsCString group = groupPrefix + groupNoSuffix;
+
+  OriginAttributes originAttributes;
+
+  nsCString originNoSuffix;
+  QM_TRY(OkIf(originAttributes.PopulateFromOrigin(aOriginMetadata.mOrigin,
+                                                  originNoSuffix)),
+         NS_ERROR_FAILURE);
+
+  nsCString originPrefix;
+  GetJarPrefix(originAttributes.mInIsolatedMozBrowser, originPrefix);
+
+  nsCString origin = originPrefix + originNoSuffix;
+
+  MOZ_ASSERT(groupPrefix == originPrefix);
+
+  QM_TRY_INSPECT(const auto& file, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsCOMPtr<nsIFile>, aDirectory, Clone));
+
+  QM_TRY(MOZ_TO_RESULT(file->Append(nsLiteralString(METADATA_TMP_FILE_NAME))));
+
+  QM_TRY_INSPECT(const auto& stream,
+                 GetBinaryOutputStream(*file, FileFlag::Truncate));
+  MOZ_ASSERT(stream);
+
+  QM_TRY(MOZ_TO_RESULT(stream->Write64(aTimestamp)));
+
+  QM_TRY(MOZ_TO_RESULT(stream->WriteStringZ(group.get())));
+
+  QM_TRY(MOZ_TO_RESULT(stream->WriteStringZ(origin.get())));
+
+  // Currently unused (used to be isApp).
+  QM_TRY(MOZ_TO_RESULT(stream->WriteBoolean(false)));
+
+  QM_TRY(MOZ_TO_RESULT(stream->Flush()));
+
+  QM_TRY(MOZ_TO_RESULT(stream->Close()));
+
+  QM_TRY(MOZ_TO_RESULT(
+      file->RenameTo(nullptr, nsLiteralString(METADATA_FILE_NAME))));
+
+  return NS_OK;
+}
+
+nsresult CreateDirectoryMetadata2(nsIFile& aDirectory, int64_t aTimestamp,
+                                  bool aPersisted,
+                                  const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& file, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsCOMPtr<nsIFile>, aDirectory, Clone));
+
+  QM_TRY(
+      MOZ_TO_RESULT(file->Append(nsLiteralString(METADATA_V2_TMP_FILE_NAME))));
+
+  QM_TRY_INSPECT(const auto& stream,
+                 GetBinaryOutputStream(*file, FileFlag::Truncate));
+  MOZ_ASSERT(stream);
+
+  QM_TRY(MOZ_TO_RESULT(stream->Write64(aTimestamp)));
+
+  QM_TRY(MOZ_TO_RESULT(stream->WriteBoolean(aPersisted)));
+
+  // Reserved data 1
+  QM_TRY(MOZ_TO_RESULT(stream->Write32(0)));
+
+  // Reserved data 2
+  QM_TRY(MOZ_TO_RESULT(stream->Write32(0)));
+
+  // The suffix isn't used right now, but we might need it in future. It's
+  // a bit of redundancy we can live with given how painful is to upgrade
+  // metadata files.
+  QM_TRY(MOZ_TO_RESULT(stream->WriteStringZ(aOriginMetadata.mSuffix.get())));
+
+  QM_TRY(MOZ_TO_RESULT(stream->WriteStringZ(aOriginMetadata.mGroup.get())));
+
+  QM_TRY(MOZ_TO_RESULT(stream->WriteStringZ(aOriginMetadata.mOrigin.get())));
+
+  // Currently unused (used to be isApp).
+  QM_TRY(MOZ_TO_RESULT(stream->WriteBoolean(false)));
+
+  QM_TRY(MOZ_TO_RESULT(stream->Flush()));
+
+  QM_TRY(MOZ_TO_RESULT(stream->Close()));
+
+  QM_TRY(MOZ_TO_RESULT(
+      file->RenameTo(nullptr, nsLiteralString(METADATA_V2_FILE_NAME))));
+
+  return NS_OK;
+}
+
+Result<nsCOMPtr<nsIBinaryInputStream>, nsresult> GetBinaryInputStream(
+    nsIFile& aDirectory, const nsAString& aFilename) {
+  MOZ_ASSERT(!NS_IsMainThread());
+
+  QM_TRY_INSPECT(const auto& file, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsCOMPtr<nsIFile>, aDirectory, Clone));
+
+  QM_TRY(MOZ_TO_RESULT(file->Append(aFilename)));
+
+  QM_TRY_UNWRAP(auto stream, NS_NewLocalFileInputStream(file));
+
+  QM_TRY_INSPECT(const auto& bufferedStream,
+                 NS_NewBufferedInputStream(stream.forget(), 512));
+
+  QM_TRY(OkIf(bufferedStream), Err(NS_ERROR_FAILURE));
+
+  return nsCOMPtr<nsIBinaryInputStream>(
+      NS_NewObjectInputStream(bufferedStream));
+}
+
+// This method computes and returns our best guess for the temporary storage
+// limit (in bytes), based on disk capacity.
+Result<uint64_t, nsresult> GetTemporaryStorageLimit(nsIFile& aStorageDir) {
+  // The fixed limit pref can be used to override temporary storage limit
+  // calculation.
+  if (StaticPrefs::dom_quotaManager_temporaryStorage_fixedLimit() >= 0) {
+    return static_cast<uint64_t>(
+               StaticPrefs::dom_quotaManager_temporaryStorage_fixedLimit()) *
+           1024;
+  }
+
+  constexpr int64_t teraByte = (1024LL * 1024LL * 1024LL * 1024LL);
+  constexpr int64_t maxAllowedCapacity = 8LL * teraByte;
+
+  // Check for disk capacity of user's device on which storage directory lives.
+  int64_t diskCapacity = maxAllowedCapacity;
+
+  // Log error when default disk capacity is returned due to the error
+  QM_WARNONLY_TRY(MOZ_TO_RESULT(aStorageDir.GetDiskCapacity(&diskCapacity)));
+
+  MOZ_ASSERT(diskCapacity >= 0LL);
+
+  // Allow temporary storage to consume up to 50% of disk capacity.
+  int64_t capacityLimit = diskCapacity / 2LL;
+
+  // If the disk capacity reported by the operating system is very
+  // large and potentially incorrect due to hardware issues,
+  // a hardcoded limit is supplied instead.
+  QM_WARNONLY_TRY(
+      OkIf(capacityLimit < maxAllowedCapacity),
+      ([&capacityLimit](const auto&) { capacityLimit = maxAllowedCapacity; }));
+
+  return capacityLimit;
+}
+
+bool IsOriginUnaccessed(const FullOriginMetadata& aFullOriginMetadata,
+                        const int64_t aRecentTime) {
+  if (aFullOriginMetadata.mLastAccessTime > aRecentTime) {
+    return false;
+  }
+
+  return (aRecentTime - aFullOriginMetadata.mLastAccessTime) / PR_USEC_PER_SEC >
+         StaticPrefs::dom_quotaManager_unaccessedForLongTimeThresholdSec();
+}
+
+}  // namespace
+
+/*******************************************************************************
+ * Exported functions
+ ******************************************************************************/
+
+void InitializeQuotaManager() {
+  MOZ_ASSERT(XRE_IsParentProcess());
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!gQuotaManagerInitialized);
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  ScopedLogExtraInfo::Initialize();
+#endif
+
+  if (!QuotaManager::IsRunningGTests()) {
+    // This service has to be started on the main thread currently.
+    const nsCOMPtr<mozIStorageService> ss =
+        do_GetService(MOZ_STORAGE_SERVICE_CONTRACTID);
+
+    QM_WARNONLY_TRY(OkIf(ss));
+  }
+
+  QM_WARNONLY_TRY(QM_TO_RESULT(QuotaManager::Initialize()));
+
+#ifdef DEBUG
+  gQuotaManagerInitialized = true;
+#endif
+}
+
+PQuotaParent* AllocPQuotaParent() {
+  AssertIsOnBackgroundThread();
+
+  if (NS_WARN_IF(QuotaManager::IsShuttingDown())) {
+    return nullptr;
+  }
+
+  auto actor = MakeRefPtr<Quota>();
+
+  return actor.forget().take();
+}
+
+bool DeallocPQuotaParent(PQuotaParent* aActor) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aActor);
+
+  RefPtr<Quota> actor = dont_AddRef(static_cast<Quota*>(aActor));
+  return true;
+}
+
+bool RecvShutdownQuotaManager() {
+  AssertIsOnBackgroundThread();
+
+  // If we are already in shutdown, don't call ShutdownInstance()
+  // again and return true immediately. We shall see this incident
+  // in Telemetry.
+  // XXX todo: Make QM_TRY stacks thread-aware (Bug 1735124)
+  // XXX todo: Active QM_TRY context for shutdown (Bug 1735170)
+  QM_TRY(OkIf(!gShutdown), true);
+
+  QuotaManager::ShutdownInstance();
+
+  return true;
+}
+
+QuotaManager::Observer* QuotaManager::Observer::sInstance = nullptr;
+
+// static
+nsresult QuotaManager::Observer::Initialize() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  RefPtr<Observer> observer = new Observer();
+
+  nsresult rv = observer->Init();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  sInstance = observer;
+
+  return NS_OK;
+}
+
+// static
+nsIObserver* QuotaManager::Observer::GetInstance() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  return sInstance;
+}
+
+// static
+void QuotaManager::Observer::ShutdownCompleted() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(sInstance);
+
+  sInstance->mShutdownComplete = true;
+}
+
+nsresult QuotaManager::Observer::Init() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  if (NS_WARN_IF(!obs)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // XXX: Improve the way that we remove observer in failure cases.
+  nsresult rv = obs->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = obs->AddObserver(this, kProfileDoChangeTopic, false);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    obs->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
+    return rv;
+  }
+
+  rv = obs->AddObserver(this, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID, false);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    obs->RemoveObserver(this, kProfileDoChangeTopic);
+    obs->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
+    return rv;
+  }
+
+  rv = obs->AddObserver(this, NS_WIDGET_WAKE_OBSERVER_TOPIC, false);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    obs->RemoveObserver(this, kProfileDoChangeTopic);
+    obs->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
+    obs->RemoveObserver(this, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID);
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+nsresult QuotaManager::Observer::Shutdown() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  if (NS_WARN_IF(!obs)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  MOZ_ALWAYS_SUCCEEDS(obs->RemoveObserver(this, NS_WIDGET_WAKE_OBSERVER_TOPIC));
+  MOZ_ALWAYS_SUCCEEDS(
+      obs->RemoveObserver(this, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID));
+  MOZ_ALWAYS_SUCCEEDS(obs->RemoveObserver(this, kProfileDoChangeTopic));
+  MOZ_ALWAYS_SUCCEEDS(obs->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID));
+
+  sInstance = nullptr;
+
+  // In general, the instance will have died after the latter removal call, so
+  // it's not safe to do anything after that point.
+  // However, Shutdown is currently called from Observe which is called by the
+  // Observer Service which holds a strong reference to the observer while the
+  // Observe method is being called.
+
+  return NS_OK;
+}
+
+NS_IMPL_ISUPPORTS(QuotaManager::Observer, nsIObserver)
+
+NS_IMETHODIMP
+QuotaManager::Observer::Observe(nsISupports* aSubject, const char* aTopic,
+                                const char16_t* aData) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv;
+
+  if (!strcmp(aTopic, kProfileDoChangeTopic)) {
+    if (NS_WARN_IF(gBasePath)) {
+      NS_WARNING(
+          "profile-before-change-qm must precede repeated "
+          "profile-do-change!");
+      return NS_OK;
+    }
+
+    Telemetry::SetEventRecordingEnabled("dom.quota.try"_ns, true);
+
+    gBasePath = new nsString();
+
+    nsCOMPtr<nsIFile> baseDir;
+    rv = NS_GetSpecialDirectory(NS_APP_INDEXEDDB_PARENT_DIR,
+                                getter_AddRefs(baseDir));
+    if (NS_FAILED(rv)) {
+      rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                                  getter_AddRefs(baseDir));
+    }
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    rv = baseDir->GetPath(*gBasePath);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    gStorageName = new nsString();
+
+    rv = Preferences::GetString("dom.quotaManager.storageName", *gStorageName);
+    if (NS_FAILED(rv)) {
+      *gStorageName = kStorageName;
+    }
+
+    gBuildId = new nsCString();
+
+    nsCOMPtr<nsIPlatformInfo> platformInfo =
+        do_GetService("@mozilla.org/xre/app-info;1");
+    if (NS_WARN_IF(!platformInfo)) {
+      return NS_ERROR_FAILURE;
+    }
+
+    rv = platformInfo->GetPlatformBuildID(*gBuildId);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID)) {
+    if (NS_WARN_IF(!gBasePath)) {
+      NS_WARNING("profile-do-change must precede profile-before-change-qm!");
+      return NS_OK;
+    }
+
+    // mPendingProfileChange is our re-entrancy guard (the nested event loop
+    // below may cause re-entrancy).
+    if (mPendingProfileChange) {
+      return NS_OK;
+    }
+
+    AutoRestore<bool> pending(mPendingProfileChange);
+    mPendingProfileChange = true;
+
+    mShutdownComplete = false;
+
+    PBackgroundChild* backgroundActor =
+        BackgroundChild::GetOrCreateForCurrentThread();
+    if (NS_WARN_IF(!backgroundActor)) {
+      return NS_ERROR_FAILURE;
+    }
+
+    if (NS_WARN_IF(!backgroundActor->SendShutdownQuotaManager())) {
+      return NS_ERROR_FAILURE;
+    }
+
+    MOZ_ALWAYS_TRUE(SpinEventLoopUntil(
+        "QuotaManager::Observer::Observe profile-before-change-qm"_ns,
+        [&]() { return mShutdownComplete; }));
+
+    gBasePath = nullptr;
+
+    gStorageName = nullptr;
+
+    gBuildId = nullptr;
+
+    Telemetry::SetEventRecordingEnabled("dom.quota.try"_ns, false);
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
+    rv = Shutdown();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, NS_WIDGET_WAKE_OBSERVER_TOPIC)) {
+    gLastOSWake = TimeStamp::Now();
+
+    return NS_OK;
+  }
+
+  NS_WARNING("Unknown observer topic!");
+  return NS_OK;
+}
+
+/*******************************************************************************
+ * Quota manager
+ ******************************************************************************/
+
+QuotaManager::QuotaManager(const nsAString& aBasePath,
+                           const nsAString& aStorageName)
+    : mQuotaMutex("QuotaManager.mQuotaMutex"),
+      mBasePath(aBasePath),
+      mStorageName(aStorageName),
+      mTemporaryStorageUsage(0),
+      mNextDirectoryLockId(0),
+      mTemporaryStorageInitialized(false),
+      mCacheUsable(false),
+      mShuttingDownStorage(false) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(!gInstance);
+}
+
+QuotaManager::~QuotaManager() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(!gInstance || gInstance == this);
+}
+
+// static
+nsresult QuotaManager::Initialize() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv = Observer::Initialize();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+// static
+Result<MovingNotNull<RefPtr<QuotaManager>>, nsresult>
+QuotaManager::GetOrCreate() {
+  AssertIsOnBackgroundThread();
+
+  if (gInstance) {
+    return WrapMovingNotNullUnchecked(RefPtr<QuotaManager>{gInstance});
+  }
+
+  QM_TRY(OkIf(gBasePath), Err(NS_ERROR_FAILURE), [](const auto&) {
+    NS_WARNING(
+        "Trying to create QuotaManager before profile-do-change! "
+        "Forgot to call do_get_profile()?");
+  });
+
+  QM_TRY(OkIf(!IsShuttingDown()), Err(NS_ERROR_FAILURE), [](const auto&) {
+    MOZ_ASSERT(false,
+               "Trying to create QuotaManager after profile-before-change-qm!");
+  });
+
+  auto instance = MakeRefPtr<QuotaManager>(*gBasePath, *gStorageName);
+
+  QM_TRY(MOZ_TO_RESULT(instance->Init()));
+
+  gInstance = instance;
+
+  return WrapMovingNotNullUnchecked(std::move(instance));
+}
+
+Result<Ok, nsresult> QuotaManager::EnsureCreated() {
+  AssertIsOnBackgroundThread();
+
+  QM_TRY_RETURN(GetOrCreate().map([](const auto& res) { return Ok{}; }))
+}
+
+// static
+QuotaManager* QuotaManager::Get() {
+  // Does not return an owning reference.
+  return gInstance;
+}
+
+// static
+nsIObserver* QuotaManager::GetObserver() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  return Observer::GetInstance();
+}
+
+// static
+bool QuotaManager::IsShuttingDown() { return gShutdown; }
+
+// static
+void QuotaManager::ShutdownInstance() {
+  AssertIsOnBackgroundThread();
+
+  if (gInstance) {
+    gInstance->Shutdown();
+
+    gInstance = nullptr;
+  }
+
+  RefPtr<Runnable> runnable =
+      NS_NewRunnableFunction("dom::quota::QuotaManager::ShutdownCompleted",
+                             []() { Observer::ShutdownCompleted(); });
+  MOZ_ASSERT(runnable);
+
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable.forget()));
+}
+
+// static
+void QuotaManager::Reset() {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(!gInstance);
+  MOZ_ASSERT(gShutdown);
+
+  gShutdown = false;
+}
+
+// static
+bool QuotaManager::IsOSMetadata(const nsAString& aFileName) {
+  return aFileName.EqualsLiteral(DSSTORE_FILE_NAME) ||
+         aFileName.EqualsLiteral(DESKTOP_FILE_NAME) ||
+         aFileName.LowerCaseEqualsLiteral(DESKTOP_INI_FILE_NAME) ||
+         aFileName.LowerCaseEqualsLiteral(THUMBS_DB_FILE_NAME);
+}
+
+// static
+bool QuotaManager::IsDotFile(const nsAString& aFileName) {
+  return aFileName.First() == char16_t('.');
+}
+
+void QuotaManager::RegisterDirectoryLock(DirectoryLockImpl& aLock) {
+  AssertIsOnOwningThread();
+
+  mDirectoryLocks.AppendElement(WrapNotNullUnchecked(&aLock));
+
+  if (aLock.ShouldUpdateLockIdTable()) {
+    MutexAutoLock lock(mQuotaMutex);
+
+    MOZ_DIAGNOSTIC_ASSERT(!mDirectoryLockIdTable.Contains(aLock.Id()));
+    mDirectoryLockIdTable.InsertOrUpdate(aLock.Id(),
+                                         WrapNotNullUnchecked(&aLock));
+  }
+
+  if (aLock.ShouldUpdateLockTable()) {
+    DirectoryLockTable& directoryLockTable =
+        GetDirectoryLockTable(aLock.GetPersistenceType());
+
+    // XXX It seems that the contents of the array are never actually used, we
+    // just use that like an inefficient use counter. Can't we just change
+    // DirectoryLockTable to a nsTHashMap<nsCStringHashKey, uint32_t>?
+    directoryLockTable
+        .LookupOrInsertWith(
+            aLock.Origin(),
+            [this, &aLock] {
+              if (!IsShuttingDown()) {
+                UpdateOriginAccessTime(aLock.GetPersistenceType(),
+                                       aLock.OriginMetadata());
+              }
+              return MakeUnique<nsTArray<NotNull<DirectoryLockImpl*>>>();
+            })
+        ->AppendElement(WrapNotNullUnchecked(&aLock));
+  }
+
+  aLock.SetRegistered(true);
+}
+
+void QuotaManager::UnregisterDirectoryLock(DirectoryLockImpl& aLock) {
+  AssertIsOnOwningThread();
+
+  MOZ_ALWAYS_TRUE(mDirectoryLocks.RemoveElement(&aLock));
+
+  if (aLock.ShouldUpdateLockIdTable()) {
+    MutexAutoLock lock(mQuotaMutex);
+
+    MOZ_DIAGNOSTIC_ASSERT(mDirectoryLockIdTable.Contains(aLock.Id()));
+    mDirectoryLockIdTable.Remove(aLock.Id());
+  }
+
+  if (aLock.ShouldUpdateLockTable()) {
+    DirectoryLockTable& directoryLockTable =
+        GetDirectoryLockTable(aLock.GetPersistenceType());
+
+    nsTArray<NotNull<DirectoryLockImpl*>>* array;
+    MOZ_ALWAYS_TRUE(directoryLockTable.Get(aLock.Origin(), &array));
+
+    MOZ_ALWAYS_TRUE(array->RemoveElement(&aLock));
+    if (array->IsEmpty()) {
+      directoryLockTable.Remove(aLock.Origin());
+
+      if (!IsShuttingDown()) {
+        UpdateOriginAccessTime(aLock.GetPersistenceType(),
+                               aLock.OriginMetadata());
+      }
+    }
+  }
+
+  aLock.SetRegistered(false);
+}
+
+void QuotaManager::AddPendingDirectoryLock(DirectoryLockImpl& aLock) {
+  AssertIsOnOwningThread();
+
+  mPendingDirectoryLocks.AppendElement(&aLock);
+}
+
+void QuotaManager::RemovePendingDirectoryLock(DirectoryLockImpl& aLock) {
+  AssertIsOnOwningThread();
+
+  MOZ_ALWAYS_TRUE(mPendingDirectoryLocks.RemoveElement(&aLock));
+}
+
+uint64_t QuotaManager::CollectOriginsForEviction(
+    uint64_t aMinSizeToBeFreed, nsTArray<RefPtr<OriginDirectoryLock>>& aLocks) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aLocks.IsEmpty());
+
+  // XXX This looks as if this could/should also use CollectLRUOriginInfosUntil,
+  // or maybe a generalization if that.
+
+  struct MOZ_STACK_CLASS Helper final {
+    static void GetInactiveOriginInfos(
+        const nsTArray<NotNull<RefPtr<OriginInfo>>>& aOriginInfos,
+        const nsTArray<NotNull<const DirectoryLockImpl*>>& aLocks,
+        OriginInfosFlatTraversable& aInactiveOriginInfos) {
+      for (const auto& originInfo : aOriginInfos) {
+        MOZ_ASSERT(originInfo->mGroupInfo->mPersistenceType !=
+                   PERSISTENCE_TYPE_PERSISTENT);
+
+        if (originInfo->LockedPersisted()) {
+          continue;
+        }
+
+        // Never evict PERSISTENCE_TYPE_DEFAULT data associated to a
+        // moz-extension origin, unlike websites (which may more likely using
+        // the local data as a cache but still able to retrieve the same data
+        // from the server side) extensions do not have the same data stored
+        // anywhere else and evicting the data would result into potential data
+        // loss for the users.
+        //
+        // Also, unlike a website the extensions are explicitly installed and
+        // uninstalled by the user and all data associated to the extension
+        // principal will be completely removed once the addon is uninstalled.
+        if (originInfo->mGroupInfo->mPersistenceType !=
+                PERSISTENCE_TYPE_TEMPORARY &&
+            originInfo->IsExtensionOrigin()) {
+          continue;
+        }
+
+        const auto originScope = OriginScope::FromOrigin(originInfo->mOrigin);
+
+        const bool match =
+            std::any_of(aLocks.begin(), aLocks.end(),
+                        [&originScope](const DirectoryLockImpl* const lock) {
+                          return originScope.Matches(lock->GetOriginScope());
+                        });
+
+        if (!match) {
+          MOZ_ASSERT(!originInfo->mCanonicalQuotaObjects.Count(),
+                     "Inactive origin shouldn't have open files!");
+          aInactiveOriginInfos.InsertElementSorted(
+              originInfo, OriginInfoAccessTimeComparator());
+        }
+      }
+    }
+  };
+
+  // Split locks into separate arrays and filter out locks for persistent
+  // storage, they can't block us.
+  const auto [temporaryStorageLocks, defaultStorageLocks] = [this] {
+    nsTArray<NotNull<const DirectoryLockImpl*>> temporaryStorageLocks;
+    nsTArray<NotNull<const DirectoryLockImpl*>> defaultStorageLocks;
+    for (NotNull<const DirectoryLockImpl*> const lock : mDirectoryLocks) {
+      const Nullable<PersistenceType>& persistenceType =
+          lock->NullablePersistenceType();
+
+      if (persistenceType.IsNull()) {
+        temporaryStorageLocks.AppendElement(lock);
+        defaultStorageLocks.AppendElement(lock);
+      } else if (persistenceType.Value() == PERSISTENCE_TYPE_TEMPORARY) {
+        temporaryStorageLocks.AppendElement(lock);
+      } else if (persistenceType.Value() == PERSISTENCE_TYPE_DEFAULT) {
+        defaultStorageLocks.AppendElement(lock);
+      } else {
+        MOZ_ASSERT(persistenceType.Value() == PERSISTENCE_TYPE_PERSISTENT);
+
+        // Do nothing here, persistent origins don't need to be collected ever.
+      }
+    }
+
+    return std::pair(std::move(temporaryStorageLocks),
+                     std::move(defaultStorageLocks));
+  }();
+
+  // Enumerate and process inactive origins. This must be protected by the
+  // mutex.
+  MutexAutoLock lock(mQuotaMutex);
+
+  const auto [inactiveOrigins, sizeToBeFreed] =
+      [this, &temporaryStorageLocks = temporaryStorageLocks,
+       &defaultStorageLocks = defaultStorageLocks, aMinSizeToBeFreed] {
+        nsTArray<NotNull<RefPtr<const OriginInfo>>> inactiveOrigins;
+        for (const auto& entry : mGroupInfoPairs) {
+          const auto& pair = entry.GetData();
+
+          MOZ_ASSERT(!entry.GetKey().IsEmpty());
+          MOZ_ASSERT(pair);
+
+          RefPtr<GroupInfo> groupInfo =
+              pair->LockedGetGroupInfo(PERSISTENCE_TYPE_TEMPORARY);
+          if (groupInfo) {
+            Helper::GetInactiveOriginInfos(groupInfo->mOriginInfos,
+                                           temporaryStorageLocks,
+                                           inactiveOrigins);
+          }
+
+          groupInfo = pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT);
+          if (groupInfo) {
+            Helper::GetInactiveOriginInfos(
+                groupInfo->mOriginInfos, defaultStorageLocks, inactiveOrigins);
+          }
+        }
+
+#ifdef DEBUG
+        // Make sure the array is sorted correctly.
+        const bool inactiveOriginsSorted =
+            std::is_sorted(inactiveOrigins.cbegin(), inactiveOrigins.cend(),
+                           [](const auto& lhs, const auto& rhs) {
+                             return lhs->mAccessTime < rhs->mAccessTime;
+                           });
+        MOZ_ASSERT(inactiveOriginsSorted);
+#endif
+
+        // Create a list of inactive and the least recently used origins
+        // whose aggregate size is greater or equals the minimal size to be
+        // freed.
+        uint64_t sizeToBeFreed = 0;
+        for (uint32_t count = inactiveOrigins.Length(), index = 0;
+             index < count; index++) {
+          if (sizeToBeFreed >= aMinSizeToBeFreed) {
+            inactiveOrigins.TruncateLength(index);
+            break;
+          }
+
+          sizeToBeFreed += inactiveOrigins[index]->LockedUsage();
+        }
+
+        return std::pair(std::move(inactiveOrigins), sizeToBeFreed);
+      }();
+
+  if (sizeToBeFreed >= aMinSizeToBeFreed) {
+    // Success, add directory locks for these origins, so any other
+    // operations for them will be delayed (until origin eviction is finalized).
+
+    for (const auto& originInfo : inactiveOrigins) {
+      auto lock = DirectoryLockImpl::CreateForEviction(
+          WrapNotNullUnchecked(this), originInfo->mGroupInfo->mPersistenceType,
+          originInfo->FlattenToOriginMetadata());
+
+      lock->AcquireImmediately();
+
+      aLocks.AppendElement(lock.forget());
+    }
+
+    return sizeToBeFreed;
+  }
+
+  return 0;
+}
+
+template <typename P>
+void QuotaManager::CollectPendingOriginsForListing(P aPredicate) {
+  MutexAutoLock lock(mQuotaMutex);
+
+  for (const auto& entry : mGroupInfoPairs) {
+    const auto& pair = entry.GetData();
+
+    MOZ_ASSERT(!entry.GetKey().IsEmpty());
+    MOZ_ASSERT(pair);
+
+    RefPtr<GroupInfo> groupInfo =
+        pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT);
+    if (groupInfo) {
+      for (const auto& originInfo : groupInfo->mOriginInfos) {
+        if (!originInfo->mDirectoryExists) {
+          aPredicate(originInfo);
+        }
+      }
+    }
+  }
+}
+
+nsresult QuotaManager::Init() {
+  AssertIsOnOwningThread();
+
+#ifdef XP_WIN
+  CacheUseDOSDevicePathSyntaxPrefValue();
+#endif
+
+  QM_TRY_INSPECT(const auto& baseDir, QM_NewLocalFile(mBasePath));
+
+  QM_TRY_UNWRAP(
+      do_Init(mIndexedDBPath),
+      GetPathForStorage(*baseDir, nsLiteralString(INDEXEDDB_DIRECTORY_NAME)));
+
+  QM_TRY(MOZ_TO_RESULT(baseDir->Append(mStorageName)));
+
+  QM_TRY_UNWRAP(do_Init(mStoragePath),
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsString, baseDir, GetPath));
+
+  QM_TRY_UNWRAP(
+      do_Init(mStorageArchivesPath),
+      GetPathForStorage(*baseDir, nsLiteralString(ARCHIVES_DIRECTORY_NAME)));
+
+  QM_TRY_UNWRAP(
+      do_Init(mPermanentStoragePath),
+      GetPathForStorage(*baseDir, nsLiteralString(PERMANENT_DIRECTORY_NAME)));
+
+  QM_TRY_UNWRAP(
+      do_Init(mTemporaryStoragePath),
+      GetPathForStorage(*baseDir, nsLiteralString(TEMPORARY_DIRECTORY_NAME)));
+
+  QM_TRY_UNWRAP(
+      do_Init(mDefaultStoragePath),
+      GetPathForStorage(*baseDir, nsLiteralString(DEFAULT_DIRECTORY_NAME)));
+
+  QM_TRY_UNWRAP(do_Init(mIOThread),
+                MOZ_TO_RESULT_INVOKE_TYPED(
+                    nsCOMPtr<nsIThread>, MOZ_SELECT_OVERLOAD(NS_NewNamedThread),
+                    "QuotaManager IO"));
+
+  static_assert(Client::IDB == 0 && Client::DOMCACHE == 1 && Client::SDB == 2 &&
+                    Client::FILESYSTEM == 3 && Client::LS == 4 &&
+                    Client::TYPE_MAX == 5,
+                "Fix the registration!");
+
+  // Register clients.
+  auto clients = decltype(mClients)::ValueType{};
+  clients.AppendElement(indexedDB::CreateQuotaClient());
+  clients.AppendElement(cache::CreateQuotaClient());
+  clients.AppendElement(simpledb::CreateQuotaClient());
+  clients.AppendElement(fs::CreateQuotaClient());
+  if (NextGenLocalStorageEnabled()) {
+    clients.AppendElement(localstorage::CreateQuotaClient());
+  } else {
+    clients.SetLength(Client::TypeMax());
+  }
+
+  mClients.init(std::move(clients));
+
+  MOZ_ASSERT(mClients->Capacity() == Client::TYPE_MAX,
+             "Should be using an auto array with correct capacity!");
+
+  mAllClientTypes.init(ClientTypesArray{
+      Client::Type::IDB, Client::Type::DOMCACHE, Client::Type::SDB,
+      Client::Type::FILESYSTEM, Client::Type::LS});
+  mAllClientTypesExceptLS.init(
+      ClientTypesArray{Client::Type::IDB, Client::Type::DOMCACHE,
+                       Client::Type::SDB, Client::Type::FILESYSTEM});
+
+  return NS_OK;
+}
+
+// static
+void QuotaManager::MaybeRecordQuotaClientShutdownStep(
+    const Client::Type aClientType, const nsACString& aStepDescription) {
+  // Callable on any thread.
+
+  auto* const quotaManager = QuotaManager::Get();
+  MOZ_DIAGNOSTIC_ASSERT(quotaManager);
+
+  if (quotaManager->IsShuttingDown()) {
+    quotaManager->RecordShutdownStep(Some(aClientType), aStepDescription);
+  }
+}
+
+// static
+void QuotaManager::SafeMaybeRecordQuotaClientShutdownStep(
+    const Client::Type aClientType, const nsACString& aStepDescription) {
+  // Callable on any thread.
+
+  auto* const quotaManager = QuotaManager::Get();
+
+  if (quotaManager && quotaManager->IsShuttingDown()) {
+    quotaManager->RecordShutdownStep(Some(aClientType), aStepDescription);
+  }
+}
+
+void QuotaManager::RecordQuotaManagerShutdownStep(
+    const nsACString& aStepDescription) {
+  // Callable on any thread.
+  MOZ_ASSERT(mShutdownStarted);
+
+  RecordShutdownStep(Nothing{}, aStepDescription);
+}
+
+void QuotaManager::MaybeRecordQuotaManagerShutdownStep(
+    const nsACString& aStepDescription) {
+  // Callable on any thread.
+
+  if (IsShuttingDown()) {
+    RecordQuotaManagerShutdownStep(aStepDescription);
+  }
+}
+
+void QuotaManager::RecordShutdownStep(const Maybe<Client::Type> aClientType,
+                                      const nsACString& aStepDescription) {
+  MOZ_ASSERT(IsShuttingDown());
+
+  const TimeDuration elapsedSinceShutdownStart =
+      TimeStamp::NowLoRes() - *mShutdownStartedAt;
+
+  const auto stepString =
+      nsPrintfCString("%fs: %s", elapsedSinceShutdownStart.ToSeconds(),
+                      nsPromiseFlatCString(aStepDescription).get());
+
+  if (aClientType) {
+    AssertIsOnBackgroundThread();
+
+    mShutdownSteps[*aClientType].Append(stepString + "\n"_ns);
+  } else {
+    // Callable on any thread.
+    MutexAutoLock lock(mQuotaMutex);
+
+    mQuotaManagerShutdownSteps.Append(stepString + "\n"_ns);
+  }
+
+#ifdef DEBUG
+  // XXX Probably this isn't the mechanism that should be used here.
+
+  NS_DebugBreak(
+      NS_DEBUG_WARNING,
+      nsAutoCString(aClientType ? Client::TypeToText(*aClientType)
+                                : "quota manager"_ns + " shutdown step"_ns)
+          .get(),
+      stepString.get(), __FILE__, __LINE__);
+#endif
+}
+
+void QuotaManager::Shutdown() {
+  AssertIsOnOwningThread();
+  MOZ_DIAGNOSTIC_ASSERT(!gShutdown);
+
+  // Define some local helper functions
+
+  auto flagShutdownStarted = [this]() {
+    // Setting this flag prevents the service from being recreated and prevents
+    // further storages from being created.
+    // XXX: Harmonize QM shutdown flags, see bug 1726714
+    gShutdown = true;
+
+    // StopIdleMaintenance used to happen before mShutdownStarted is set true
+    // but it is just an internal flag for the recording of shutdown steps
+    // and not evaluated elsewhere.
+
+    mShutdownStartedAt.init(TimeStamp::NowLoRes());
+    mShutdownStarted = true;
+  };
+
+  nsCOMPtr<nsITimer> crashBrowserTimer;
+
+  auto crashBrowserTimerCallback = [](nsITimer* aTimer, void* aClosure) {
+    auto* const quotaManager = static_cast<QuotaManager*>(aClosure);
+
+    nsCString annotation;
+
+    for (Client::Type type : quotaManager->AllClientTypes()) {
+      auto& quotaClient = *(*quotaManager->mClients)[type];
+
+      if (!quotaClient.IsShutdownCompleted()) {
+        annotation.AppendPrintf("%s: %s\nIntermediate steps:\n%s\n\n",
+                                Client::TypeToText(type).get(),
+                                quotaClient.GetShutdownStatus().get(),
+                                quotaManager->mShutdownSteps[type].get());
+      }
+    }
+
+    if (gNormalOriginOps) {
+      annotation.AppendPrintf("QM: %zu normal origin ops pending\n",
+                              gNormalOriginOps->Length());
+#ifdef MOZ_COLLECTING_RUNNABLE_TELEMETRY
+      for (const auto& op : *gNormalOriginOps) {
+        nsCString name;
+        op->GetName(name);
+        annotation.AppendPrintf("Op: %s pending\n", name.get());
+      }
+#endif
+    }
+    {
+      MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+      annotation.AppendPrintf("Intermediate steps:\n%s\n",
+                              quotaManager->mQuotaManagerShutdownSteps.get());
+    }
+
+    CrashReporter::AnnotateCrashReport(
+        CrashReporter::Annotation::QuotaManagerShutdownTimeout, annotation);
+
+    MOZ_CRASH("Quota manager shutdown timed out");
+  };
+
+  auto startCrashBrowserTimer = [&]() {
+    crashBrowserTimer = NS_NewTimer();
+    MOZ_ASSERT(crashBrowserTimer);
+    if (crashBrowserTimer) {
+      RecordQuotaManagerShutdownStep("startCrashBrowserTimer"_ns);
+      MOZ_ALWAYS_SUCCEEDS(crashBrowserTimer->InitWithNamedFuncCallback(
+          crashBrowserTimerCallback, this, SHUTDOWN_CRASH_BROWSER_TIMEOUT_MS,
+          nsITimer::TYPE_ONE_SHOT,
+          "quota::QuotaManager::Shutdown::crashBrowserTimer"));
+    }
+  };
+
+  auto stopCrashBrowserTimer = [&]() {
+    if (crashBrowserTimer) {
+      RecordQuotaManagerShutdownStep("stopCrashBrowserTimer"_ns);
+      QM_WARNONLY_TRY(QM_TO_RESULT(crashBrowserTimer->Cancel()));
+    }
+  };
+
+  auto initiateShutdownWorkThreads = [this]() {
+    RecordQuotaManagerShutdownStep("initiateShutdownWorkThreads"_ns);
+    bool needsToWait = false;
+    for (Client::Type type : AllClientTypes()) {
+      // Clients are supposed to also AbortAllOperations from this point on
+      // to speed up shutdown, if possible. Thus pending operations
+      // might not be executed anymore.
+      needsToWait |= (*mClients)[type]->InitiateShutdownWorkThreads();
+    }
+
+    return needsToWait;
+  };
+
+  nsCOMPtr<nsITimer> killActorsTimer;
+
+  auto killActorsTimerCallback = [](nsITimer* aTimer, void* aClosure) {
+    auto* const quotaManager = static_cast<QuotaManager*>(aClosure);
+
+    quotaManager->RecordQuotaManagerShutdownStep("killActorsTimerCallback"_ns);
+
+    // XXX: This abort is a workaround to unblock shutdown, which
+    // ought to be removed by bug 1682326. We probably need more
+    // checks to immediately abort new operations during
+    // shutdown.
+    quotaManager->GetClient(Client::IDB)->AbortAllOperations();
+
+    for (Client::Type type : quotaManager->AllClientTypes()) {
+      quotaManager->GetClient(type)->ForceKillActors();
+    }
+  };
+
+  auto startKillActorsTimer = [&]() {
+    killActorsTimer = NS_NewTimer();
+    MOZ_ASSERT(killActorsTimer);
+    if (killActorsTimer) {
+      RecordQuotaManagerShutdownStep("startKillActorsTimer"_ns);
+      MOZ_ALWAYS_SUCCEEDS(killActorsTimer->InitWithNamedFuncCallback(
+          killActorsTimerCallback, this, SHUTDOWN_KILL_ACTORS_TIMEOUT_MS,
+          nsITimer::TYPE_ONE_SHOT,
+          "quota::QuotaManager::Shutdown::killActorsTimer"));
+    }
+  };
+
+  auto stopKillActorsTimer = [&]() {
+    if (killActorsTimer) {
+      RecordQuotaManagerShutdownStep("stopKillActorsTimer"_ns);
+      QM_WARNONLY_TRY(QM_TO_RESULT(killActorsTimer->Cancel()));
+    }
+  };
+
+  auto isAllClientsShutdownComplete = [this] {
+    return std::all_of(AllClientTypes().cbegin(), AllClientTypes().cend(),
+                       [&self = *this](const auto type) {
+                         return (*self.mClients)[type]->IsShutdownCompleted();
+                       });
+  };
+
+  auto shutdownAndJoinWorkThreads = [this]() {
+    RecordQuotaManagerShutdownStep("shutdownAndJoinWorkThreads"_ns);
+    for (Client::Type type : AllClientTypes()) {
+      (*mClients)[type]->FinalizeShutdownWorkThreads();
+    }
+  };
+
+  auto shutdownAndJoinIOThread = [this]() {
+    RecordQuotaManagerShutdownStep("shutdownAndJoinIOThread"_ns);
+
+    // Make sure to join with our IO thread.
+    QM_WARNONLY_TRY(QM_TO_RESULT((*mIOThread)->Shutdown()));
+  };
+
+  auto invalidatePendingDirectoryLocks = [this]() {
+    RecordQuotaManagerShutdownStep("invalidatePendingDirectoryLocks"_ns);
+    for (RefPtr<DirectoryLockImpl>& lock : mPendingDirectoryLocks) {
+      lock->Invalidate();
+    }
+  };
+
+  // Body of the function
+  ScopedLogExtraInfo scope{ScopedLogExtraInfo::kTagContext,
+                           "dom::quota::QuotaManager::Shutdown"_ns};
+
+  // This must be called before `flagShutdownStarted`, it would fail otherwise.
+  // `ShutdownStorageOp` needs to acquire an exclusive directory lock over
+  // entire <profile>/storage which will abort any existing operations and wait
+  // for all existing directory locks to be released. So the shutdown operation
+  // will effectively run after all existing operations.
+  // We don't need to use the returned promise here because `ShutdownStorage`
+  // registers `ShudownStorageOp` in `gNormalOriginOps`.
+  ShutdownStorage();
+
+  flagShutdownStarted();
+
+  startCrashBrowserTimer();
+
+  // XXX: StopIdleMaintenance now just notifies all clients to abort any
+  // maintenance work.
+  // This could be done as part of QuotaClient::AbortAllOperations.
+  StopIdleMaintenance();
+
+  // XXX In theory, we could simplify the code below (and also the `Client`
+  // interface) by removing the `initiateShutdownWorkThreads` and
+  // `isAllClientsShutdownComplete` calls because it should be sufficient
+  // to rely on `ShutdownStorage` to abort all existing operations and to
+  // wait for all existing directory locks to be released as well.
+
+  const bool needsToWait =
+      initiateShutdownWorkThreads() || static_cast<bool>(gNormalOriginOps);
+
+  // If any clients cannot shutdown immediately, spin the event loop while we
+  // wait on all the threads to close.
+  if (needsToWait) {
+    startKillActorsTimer();
+
+    MOZ_ALWAYS_TRUE(SpinEventLoopUntil(
+        "QuotaManager::Shutdown"_ns, [isAllClientsShutdownComplete]() {
+          return !gNormalOriginOps && isAllClientsShutdownComplete();
+        }));
+
+    stopKillActorsTimer();
+  }
+
+  shutdownAndJoinWorkThreads();
+
+  shutdownAndJoinIOThread();
+
+  invalidatePendingDirectoryLocks();
+
+  stopCrashBrowserTimer();
+}
+
+void QuotaManager::InitQuotaForOrigin(
+    const FullOriginMetadata& aFullOriginMetadata,
+    const ClientUsageArray& aClientUsages, uint64_t aUsageBytes) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(IsBestEffortPersistenceType(aFullOriginMetadata.mPersistenceType));
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<GroupInfo> groupInfo = LockedGetOrCreateGroupInfo(
+      aFullOriginMetadata.mPersistenceType, aFullOriginMetadata.mSuffix,
+      aFullOriginMetadata.mGroup);
+
+  groupInfo->LockedAddOriginInfo(MakeNotNull<RefPtr<OriginInfo>>(
+      groupInfo, aFullOriginMetadata.mOrigin, aClientUsages, aUsageBytes,
+      aFullOriginMetadata.mLastAccessTime, aFullOriginMetadata.mPersisted,
+      /* aDirectoryExists */ true));
+}
+
+void QuotaManager::EnsureQuotaForOrigin(const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(IsBestEffortPersistenceType(aOriginMetadata.mPersistenceType));
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<GroupInfo> groupInfo = LockedGetOrCreateGroupInfo(
+      aOriginMetadata.mPersistenceType, aOriginMetadata.mSuffix,
+      aOriginMetadata.mGroup);
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+  if (!originInfo) {
+    groupInfo->LockedAddOriginInfo(MakeNotNull<RefPtr<OriginInfo>>(
+        groupInfo, aOriginMetadata.mOrigin, ClientUsageArray(),
+        /* aUsageBytes */ 0,
+        /* aAccessTime */ PR_Now(), /* aPersisted */ false,
+        /* aDirectoryExists */ false));
+  }
+}
+
+int64_t QuotaManager::NoteOriginDirectoryCreated(
+    const OriginMetadata& aOriginMetadata, bool aPersisted) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(IsBestEffortPersistenceType(aOriginMetadata.mPersistenceType));
+
+  int64_t timestamp;
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<GroupInfo> groupInfo = LockedGetOrCreateGroupInfo(
+      aOriginMetadata.mPersistenceType, aOriginMetadata.mSuffix,
+      aOriginMetadata.mGroup);
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+  if (originInfo) {
+    timestamp = originInfo->LockedAccessTime();
+    originInfo->mPersisted = aPersisted;
+    originInfo->mDirectoryExists = true;
+  } else {
+    timestamp = PR_Now();
+    groupInfo->LockedAddOriginInfo(MakeNotNull<RefPtr<OriginInfo>>(
+        groupInfo, aOriginMetadata.mOrigin, ClientUsageArray(),
+        /* aUsageBytes */ 0,
+        /* aAccessTime */ timestamp, aPersisted, /* aDirectoryExists */ true));
+  }
+
+  return timestamp;
+}
+
+void QuotaManager::DecreaseUsageForClient(const ClientMetadata& aClientMetadata,
+                                          int64_t aSize) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(IsBestEffortPersistenceType(aClientMetadata.mPersistenceType));
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  GroupInfoPair* pair;
+  if (!mGroupInfoPairs.Get(aClientMetadata.mGroup, &pair)) {
+    return;
+  }
+
+  RefPtr<GroupInfo> groupInfo =
+      pair->LockedGetGroupInfo(aClientMetadata.mPersistenceType);
+  if (!groupInfo) {
+    return;
+  }
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aClientMetadata.mOrigin);
+  if (originInfo) {
+    originInfo->LockedDecreaseUsage(aClientMetadata.mClientType, aSize);
+  }
+}
+
+void QuotaManager::ResetUsageForClient(const ClientMetadata& aClientMetadata) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(IsBestEffortPersistenceType(aClientMetadata.mPersistenceType));
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  GroupInfoPair* pair;
+  if (!mGroupInfoPairs.Get(aClientMetadata.mGroup, &pair)) {
+    return;
+  }
+
+  RefPtr<GroupInfo> groupInfo =
+      pair->LockedGetGroupInfo(aClientMetadata.mPersistenceType);
+  if (!groupInfo) {
+    return;
+  }
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aClientMetadata.mOrigin);
+  if (originInfo) {
+    originInfo->LockedResetUsageForClient(aClientMetadata.mClientType);
+  }
+}
+
+UsageInfo QuotaManager::GetUsageForClient(PersistenceType aPersistenceType,
+                                          const OriginMetadata& aOriginMetadata,
+                                          Client::Type aClientType) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  GroupInfoPair* pair;
+  if (!mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+    return UsageInfo{};
+  }
+
+  RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(aPersistenceType);
+  if (!groupInfo) {
+    return UsageInfo{};
+  }
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+  if (!originInfo) {
+    return UsageInfo{};
+  }
+
+  return originInfo->LockedGetUsageForClient(aClientType);
+}
+
+void QuotaManager::UpdateOriginAccessTime(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+  MOZ_ASSERT(!IsShuttingDown());
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  GroupInfoPair* pair;
+  if (!mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+    return;
+  }
+
+  RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(aPersistenceType);
+  if (!groupInfo) {
+    return;
+  }
+
+  RefPtr<OriginInfo> originInfo =
+      groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+  if (originInfo) {
+    int64_t timestamp = PR_Now();
+    originInfo->LockedUpdateAccessTime(timestamp);
+
+    MutexAutoUnlock autoUnlock(mQuotaMutex);
+
+    auto op = MakeRefPtr<SaveOriginAccessTimeOp>(
+        aPersistenceType, aOriginMetadata.mOrigin, timestamp);
+
+    RegisterNormalOriginOp(*op);
+
+    op->RunImmediately();
+  }
+}
+
+void QuotaManager::RemoveQuota() {
+  AssertIsOnIOThread();
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  for (const auto& entry : mGroupInfoPairs) {
+    const auto& pair = entry.GetData();
+
+    MOZ_ASSERT(!entry.GetKey().IsEmpty());
+    MOZ_ASSERT(pair);
+
+    RefPtr<GroupInfo> groupInfo =
+        pair->LockedGetGroupInfo(PERSISTENCE_TYPE_TEMPORARY);
+    if (groupInfo) {
+      groupInfo->LockedRemoveOriginInfos();
+    }
+
+    groupInfo = pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT);
+    if (groupInfo) {
+      groupInfo->LockedRemoveOriginInfos();
+    }
+  }
+
+  mGroupInfoPairs.Clear();
+
+  MOZ_ASSERT(mTemporaryStorageUsage == 0, "Should be zero!");
+}
+
+nsresult QuotaManager::LoadQuota() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mStorageConnection);
+  MOZ_ASSERT(!mTemporaryStorageInitialized);
+
+  // A list of all unaccessed default or temporary origins.
+  nsTArray<FullOriginMetadata> unaccessedOrigins;
+
+  auto MaybeCollectUnaccessedOrigin =
+      [loadQuotaInfoStartTime = PR_Now(),
+       &unaccessedOrigins](auto& fullOriginMetadata) {
+        if (IsOriginUnaccessed(fullOriginMetadata, loadQuotaInfoStartTime)) {
+          unaccessedOrigins.AppendElement(std::move(fullOriginMetadata));
+        }
+      };
+
+  auto recordQuotaInfoLoadTimeHelper =
+      MakeRefPtr<RecordQuotaInfoLoadTimeHelper>();
+
+  const auto startTime = recordQuotaInfoLoadTimeHelper->Start();
+
+  auto LoadQuotaFromCache = [&]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& stmt,
+        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+            nsCOMPtr<mozIStorageStatement>, mStorageConnection, CreateStatement,
+            "SELECT repository_id, suffix, group_, "
+            "origin, client_usages, usage, "
+            "last_access_time, accessed, persisted "
+            "FROM origin"_ns));
+
+    auto autoRemoveQuota = MakeScopeExit([&] {
+      RemoveQuota();
+      unaccessedOrigins.Clear();
+    });
+
+    QM_TRY(quota::CollectWhileHasResult(
+        *stmt,
+        [this,
+         &MaybeCollectUnaccessedOrigin](auto& stmt) -> Result<Ok, nsresult> {
+          QM_TRY_INSPECT(const int32_t& repositoryId,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 0));
+
+          const auto maybePersistenceType =
+              PersistenceTypeFromInt32(repositoryId, fallible);
+          QM_TRY(OkIf(maybePersistenceType.isSome()), Err(NS_ERROR_FAILURE));
+
+          FullOriginMetadata fullOriginMetadata;
+
+          fullOriginMetadata.mPersistenceType = maybePersistenceType.value();
+
+          QM_TRY_UNWRAP(fullOriginMetadata.mSuffix,
+                        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, stmt,
+                                                          GetUTF8String, 1));
+
+          QM_TRY_UNWRAP(fullOriginMetadata.mGroup,
+                        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, stmt,
+                                                          GetUTF8String, 2));
+
+          QM_TRY_UNWRAP(fullOriginMetadata.mOrigin,
+                        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, stmt,
+                                                          GetUTF8String, 3));
+
+          QM_TRY_INSPECT(const auto& clientUsagesText,
+                         MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, stmt,
+                                                           GetUTF8String, 4));
+
+          ClientUsageArray clientUsages;
+          QM_TRY(MOZ_TO_RESULT(clientUsages.Deserialize(clientUsagesText)));
+
+          QM_TRY_INSPECT(const int64_t& usage,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt64, 5));
+          QM_TRY_UNWRAP(fullOriginMetadata.mLastAccessTime,
+                        MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt64, 6));
+          QM_TRY_INSPECT(const int64_t& accessed,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 7));
+          QM_TRY_UNWRAP(fullOriginMetadata.mPersisted,
+                        MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 8));
+
+          QM_TRY_INSPECT(const bool& groupUpdated,
+                         MaybeUpdateGroupForOrigin(fullOriginMetadata));
+
+          Unused << groupUpdated;
+
+          QM_TRY_INSPECT(
+              const bool& lastAccessTimeUpdated,
+              MaybeUpdateLastAccessTimeForOrigin(fullOriginMetadata));
+
+          Unused << lastAccessTimeUpdated;
+
+          // We don't need to update the .metadata-v2 file on disk here,
+          // EnsureTemporaryOriginIsInitialized is responsible for doing that.
+          // We just need to use correct group and last access time before
+          // initializing quota for the given origin. (Note that calling
+          // LoadFullOriginMetadataWithRestore below might update the group in
+          // the metadata file, but only as a side-effect. The actual place we
+          // ensure consistency is in EnsureTemporaryOriginIsInitialized.)
+
+          if (accessed) {
+            QM_TRY_INSPECT(
+                const auto& directory,
+                GetDirectoryForOrigin(fullOriginMetadata.mPersistenceType,
+                                      fullOriginMetadata.mOrigin));
+
+            QM_TRY_INSPECT(const bool& exists,
+                           MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists));
+
+            QM_TRY(OkIf(exists), Err(NS_ERROR_FAILURE));
+
+            QM_TRY_INSPECT(const bool& isDirectory,
+                           MOZ_TO_RESULT_INVOKE_MEMBER(directory, IsDirectory));
+
+            QM_TRY(OkIf(isDirectory), Err(NS_ERROR_FAILURE));
+
+            // Calling LoadFullOriginMetadataWithRestore might update the group
+            // in the metadata file, but only as a side-effect. The actual place
+            // we ensure consistency is in EnsureTemporaryOriginIsInitialized.
+
+            QM_TRY_INSPECT(const auto& metadata,
+                           LoadFullOriginMetadataWithRestore(directory));
+
+            QM_TRY(OkIf(fullOriginMetadata.mLastAccessTime ==
+                        metadata.mLastAccessTime),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(OkIf(fullOriginMetadata.mPersisted == metadata.mPersisted),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(OkIf(fullOriginMetadata.mPersistenceType ==
+                        metadata.mPersistenceType),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(OkIf(fullOriginMetadata.mSuffix == metadata.mSuffix),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(OkIf(fullOriginMetadata.mGroup == metadata.mGroup),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(OkIf(fullOriginMetadata.mOrigin == metadata.mOrigin),
+                   Err(NS_ERROR_FAILURE));
+
+            QM_TRY(MOZ_TO_RESULT(InitializeOrigin(
+                fullOriginMetadata.mPersistenceType, fullOriginMetadata,
+                fullOriginMetadata.mLastAccessTime,
+                fullOriginMetadata.mPersisted, directory)));
+          } else {
+            InitQuotaForOrigin(fullOriginMetadata, clientUsages, usage);
+          }
+
+          MaybeCollectUnaccessedOrigin(fullOriginMetadata);
+
+          return Ok{};
+        }));
+
+    autoRemoveQuota.release();
+
+    return NS_OK;
+  };
+
+  QM_TRY_INSPECT(
+      const bool& loadQuotaFromCache, ([this]() -> Result<bool, nsresult> {
+        if (mCacheUsable) {
+          QM_TRY_INSPECT(
+              const auto& stmt,
+              CreateAndExecuteSingleStepStatement<
+                  SingleStepResult::ReturnNullIfNoResult>(
+                  *mStorageConnection, "SELECT valid, build_id FROM cache"_ns));
+
+          QM_TRY(OkIf(stmt), Err(NS_ERROR_FILE_CORRUPTED));
+
+          QM_TRY_INSPECT(const int32_t& valid,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(stmt, GetInt32, 0));
+
+          if (valid) {
+            if (!StaticPrefs::dom_quotaManager_caching_checkBuildId()) {
+              return true;
+            }
+
+            QM_TRY_INSPECT(const auto& buildId,
+                           MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                               nsAutoCString, stmt, GetUTF8String, 1));
+
+            return buildId == *gBuildId;
+          }
+        }
+
+        return false;
+      }()));
+
+  auto autoRemoveQuota = MakeScopeExit([&] { RemoveQuota(); });
+
+  if (!loadQuotaFromCache ||
+      !StaticPrefs::dom_quotaManager_loadQuotaFromCache() ||
+      ![&LoadQuotaFromCache] {
+        QM_WARNONLY_TRY_UNWRAP(auto res, MOZ_TO_RESULT(LoadQuotaFromCache()));
+        return static_cast<bool>(res);
+      }()) {
+    // A keeper to defer the return only in Nightly, so that the telemetry data
+    // for whole profile can be collected.
+#ifdef NIGHTLY_BUILD
+    nsresult statusKeeper = NS_OK;
+#endif
+
+    const auto statusKeeperFunc = [&](const nsresult rv) {
+      RECORD_IN_NIGHTLY(statusKeeper, rv);
+    };
+
+    for (const PersistenceType type : kBestEffortPersistenceTypes) {
+      if (NS_WARN_IF(IsShuttingDown())) {
+        RETURN_STATUS_OR_RESULT(statusKeeper, NS_ERROR_ABORT);
+      }
+
+      QM_TRY(([&]() -> Result<Ok, nsresult> {
+        QM_TRY(MOZ_TO_RESULT(([this, type, &MaybeCollectUnaccessedOrigin] {
+                 const auto innerFunc = [&](const auto&) -> nsresult {
+                   return InitializeRepository(type,
+                                               MaybeCollectUnaccessedOrigin);
+                 };
+
+                 return ExecuteInitialization(
+                     type == PERSISTENCE_TYPE_DEFAULT
+                         ? Initialization::DefaultRepository
+                         : Initialization::TemporaryRepository,
+                     innerFunc);
+               }())),
+               OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+        return Ok{};
+      }()));
+    }
+
+#ifdef NIGHTLY_BUILD
+    if (NS_FAILED(statusKeeper)) {
+      return statusKeeper;
+    }
+#endif
+  }
+
+  autoRemoveQuota.release();
+
+  const auto endTime = recordQuotaInfoLoadTimeHelper->End();
+
+  if (StaticPrefs::dom_quotaManager_checkQuotaInfoLoadTime() &&
+      static_cast<uint32_t>((endTime - startTime).ToMilliseconds()) >=
+          StaticPrefs::dom_quotaManager_longQuotaInfoLoadTimeThresholdMs() &&
+      !unaccessedOrigins.IsEmpty()) {
+    QM_WARNONLY_TRY(ArchiveOrigins(unaccessedOrigins));
+  }
+
+  return NS_OK;
+}
+
+void QuotaManager::UnloadQuota() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mStorageConnection);
+  MOZ_ASSERT(mTemporaryStorageInitialized);
+  MOZ_ASSERT(mCacheUsable);
+
+  auto autoRemoveQuota = MakeScopeExit([&] { RemoveQuota(); });
+
+  mozStorageTransaction transaction(
+      mStorageConnection, false, mozIStorageConnection::TRANSACTION_IMMEDIATE);
+
+  QM_TRY(MOZ_TO_RESULT(transaction.Start()), QM_VOID);
+
+  QM_TRY(MOZ_TO_RESULT(
+             mStorageConnection->ExecuteSimpleSQL("DELETE FROM origin;"_ns)),
+         QM_VOID);
+
+  nsCOMPtr<mozIStorageStatement> insertStmt;
+
+  {
+    MutexAutoLock lock(mQuotaMutex);
+
+    for (auto iter = mGroupInfoPairs.Iter(); !iter.Done(); iter.Next()) {
+      MOZ_ASSERT(!iter.Key().IsEmpty());
+
+      GroupInfoPair* const pair = iter.UserData();
+      MOZ_ASSERT(pair);
+
+      for (const PersistenceType type : kBestEffortPersistenceTypes) {
+        RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(type);
+        if (!groupInfo) {
+          continue;
+        }
+
+        for (const auto& originInfo : groupInfo->mOriginInfos) {
+          MOZ_ASSERT(!originInfo->mCanonicalQuotaObjects.Count());
+
+          if (!originInfo->mDirectoryExists) {
+            continue;
+          }
+
+          if (insertStmt) {
+            MOZ_ALWAYS_SUCCEEDS(insertStmt->Reset());
+          } else {
+            QM_TRY_UNWRAP(
+                insertStmt,
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                    nsCOMPtr<mozIStorageStatement>, mStorageConnection,
+                    CreateStatement,
+                    "INSERT INTO origin (repository_id, suffix, group_, "
+                    "origin, client_usages, usage, last_access_time, "
+                    "accessed, persisted) "
+                    "VALUES (:repository_id, :suffix, :group_, :origin, "
+                    ":client_usages, :usage, :last_access_time, :accessed, "
+                    ":persisted)"_ns),
+                QM_VOID);
+          }
+
+          QM_TRY(MOZ_TO_RESULT(originInfo->LockedBindToStatement(insertStmt)),
+                 QM_VOID);
+
+          QM_TRY(MOZ_TO_RESULT(insertStmt->Execute()), QM_VOID);
+        }
+
+        groupInfo->LockedRemoveOriginInfos();
+      }
+
+      iter.Remove();
+    }
+  }
+
+  QM_TRY_INSPECT(
+      const auto& stmt,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+          nsCOMPtr<mozIStorageStatement>, mStorageConnection, CreateStatement,
+          "UPDATE cache SET valid = :valid, build_id = :buildId;"_ns),
+      QM_VOID);
+
+  QM_TRY(MOZ_TO_RESULT(stmt->BindInt32ByName("valid"_ns, 1)), QM_VOID);
+  QM_TRY(MOZ_TO_RESULT(stmt->BindUTF8StringByName("buildId"_ns, *gBuildId)),
+         QM_VOID);
+  QM_TRY(MOZ_TO_RESULT(stmt->Execute()), QM_VOID);
+  QM_TRY(MOZ_TO_RESULT(transaction.Commit()), QM_VOID);
+}
+
+already_AddRefed<QuotaObject> QuotaManager::GetQuotaObject(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+    Client::Type aClientType, nsIFile* aFile, int64_t aFileSize,
+    int64_t* aFileSizeOut /* = nullptr */) {
+  NS_ASSERTION(!NS_IsMainThread(), "Wrong thread!");
+
+  if (aFileSizeOut) {
+    *aFileSizeOut = 0;
+  }
+
+  if (aPersistenceType == PERSISTENCE_TYPE_PERSISTENT) {
+    return nullptr;
+  }
+
+  QM_TRY_INSPECT(const auto& path,
+                 MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsString, aFile, GetPath),
+                 nullptr);
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(
+        const auto& directory,
+        GetDirectoryForOrigin(aPersistenceType, aOriginMetadata.mOrigin),
+        nullptr);
+
+    nsAutoString clientType;
+    QM_TRY(OkIf(Client::TypeToText(aClientType, clientType, fallible)),
+           nullptr);
+
+    QM_TRY(MOZ_TO_RESULT(directory->Append(clientType)), nullptr);
+
+    QM_TRY_INSPECT(
+        const auto& directoryPath,
+        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsString, directory, GetPath),
+        nullptr);
+
+    MOZ_ASSERT(StringBeginsWith(path, directoryPath));
+  }
+#endif
+
+  QM_TRY_INSPECT(
+      const int64_t fileSize,
+      ([&aFile, aFileSize]() -> Result<int64_t, nsresult> {
+        if (aFileSize == -1) {
+          QM_TRY_INSPECT(const bool& exists,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(aFile, Exists));
+
+          if (exists) {
+            QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER(aFile, GetFileSize));
+          }
+
+          return 0;
+        }
+
+        return aFileSize;
+      }()),
+      nullptr);
+
+  RefPtr<QuotaObject> result;
+  {
+    MutexAutoLock lock(mQuotaMutex);
+
+    GroupInfoPair* pair;
+    if (!mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+      return nullptr;
+    }
+
+    RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(aPersistenceType);
+
+    if (!groupInfo) {
+      return nullptr;
+    }
+
+    RefPtr<OriginInfo> originInfo =
+        groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+
+    if (!originInfo) {
+      return nullptr;
+    }
+
+    // We need this extra raw pointer because we can't assign to the smart
+    // pointer directly since QuotaObject::AddRef would try to acquire the same
+    // mutex.
+    const NotNull<CanonicalQuotaObject*> canonicalQuotaObject =
+        originInfo->mCanonicalQuotaObjects.LookupOrInsertWith(path, [&] {
+          // Create a new QuotaObject. The hashtable is not responsible to
+          // delete the QuotaObject.
+          return WrapNotNullUnchecked(new CanonicalQuotaObject(
+              originInfo, aClientType, path, fileSize));
+        });
+
+    // Addref the QuotaObject and move the ownership to the result. This must
+    // happen before we unlock!
+    result = canonicalQuotaObject->LockedAddRef();
+  }
+
+  if (aFileSizeOut) {
+    *aFileSizeOut = fileSize;
+  }
+
+  // The caller becomes the owner of the QuotaObject, that is, the caller is
+  // is responsible to delete it when the last reference is removed.
+  return result.forget();
+}
+
+already_AddRefed<QuotaObject> QuotaManager::GetQuotaObject(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+    Client::Type aClientType, const nsAString& aPath, int64_t aFileSize,
+    int64_t* aFileSizeOut /* = nullptr */) {
+  NS_ASSERTION(!NS_IsMainThread(), "Wrong thread!");
+
+  if (aFileSizeOut) {
+    *aFileSizeOut = 0;
+  }
+
+  QM_TRY_INSPECT(const auto& file, QM_NewLocalFile(aPath), nullptr);
+
+  return GetQuotaObject(aPersistenceType, aOriginMetadata, aClientType, file,
+                        aFileSize, aFileSizeOut);
+}
+
+already_AddRefed<QuotaObject> QuotaManager::GetQuotaObject(
+    const int64_t aDirectoryLockId, const nsAString& aPath) {
+  NS_ASSERTION(!NS_IsMainThread(), "Wrong thread!");
+
+  Maybe<MutexAutoLock> lock;
+
+  // See the comment for mDirectoryLockIdTable in QuotaManager.h
+  if (!IsOnBackgroundThread()) {
+    lock.emplace(mQuotaMutex);
+  }
+
+  if (auto maybeDirectoryLock =
+          mDirectoryLockIdTable.MaybeGet(aDirectoryLockId)) {
+    const auto& directoryLock = *maybeDirectoryLock;
+    MOZ_DIAGNOSTIC_ASSERT(directoryLock->ShouldUpdateLockIdTable());
+
+    const PersistenceType persistenceType = directoryLock->GetPersistenceType();
+    const OriginMetadata& originMetadata = directoryLock->OriginMetadata();
+    const Client::Type clientType = directoryLock->ClientType();
+
+    lock.reset();
+
+    return GetQuotaObject(persistenceType, originMetadata, clientType, aPath);
+  }
+
+  MOZ_CRASH("Getting quota object for an unregistered directory lock?");
+}
+
+Nullable<bool> QuotaManager::OriginPersisted(
+    const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<OriginInfo> originInfo =
+      LockedGetOriginInfo(PERSISTENCE_TYPE_DEFAULT, aOriginMetadata);
+  if (originInfo) {
+    return Nullable<bool>(originInfo->LockedPersisted());
+  }
+
+  return Nullable<bool>();
+}
+
+void QuotaManager::PersistOrigin(const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<OriginInfo> originInfo =
+      LockedGetOriginInfo(PERSISTENCE_TYPE_DEFAULT, aOriginMetadata);
+  if (originInfo && !originInfo->LockedPersisted()) {
+    originInfo->LockedPersist();
+  }
+}
+
+void QuotaManager::AbortOperationsForLocks(
+    const DirectoryLockIdTableArray& aLockIds) {
+  for (Client::Type type : AllClientTypes()) {
+    if (aLockIds[type].Filled()) {
+      (*mClients)[type]->AbortOperationsForLocks(aLockIds[type]);
+    }
+  }
+}
+
+void QuotaManager::AbortOperationsForProcess(ContentParentId aContentParentId) {
+  AssertIsOnOwningThread();
+
+  for (const RefPtr<Client>& client : *mClients) {
+    client->AbortOperationsForProcess(aContentParentId);
+  }
+}
+
+Result<nsCOMPtr<nsIFile>, nsresult> QuotaManager::GetDirectoryForOrigin(
+    PersistenceType aPersistenceType, const nsACString& aASCIIOrigin) const {
+  QM_TRY_UNWRAP(auto directory,
+                QM_NewLocalFile(GetStoragePath(aPersistenceType)));
+
+  QM_TRY(MOZ_TO_RESULT(
+      directory->Append(MakeSanitizedOriginString(aASCIIOrigin))));
+
+  return directory;
+}
+
+nsresult QuotaManager::RestoreDirectoryMetadata2(nsIFile* aDirectory) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aDirectory);
+  MOZ_ASSERT(mStorageConnection);
+
+  RefPtr<RestoreDirectoryMetadata2Helper> helper =
+      new RestoreDirectoryMetadata2Helper(aDirectory);
+
+  QM_TRY(MOZ_TO_RESULT(helper->Init()));
+
+  QM_TRY(MOZ_TO_RESULT(helper->RestoreMetadata2File()));
+
+  return NS_OK;
+}
+
+Result<FullOriginMetadata, nsresult> QuotaManager::LoadFullOriginMetadata(
+    nsIFile* aDirectory, PersistenceType aPersistenceType) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(aDirectory);
+  MOZ_ASSERT(mStorageConnection);
+
+  QM_TRY_INSPECT(const auto& binaryStream,
+                 GetBinaryInputStream(*aDirectory,
+                                      nsLiteralString(METADATA_V2_FILE_NAME)));
+
+  FullOriginMetadata fullOriginMetadata;
+
+  QM_TRY_UNWRAP(fullOriginMetadata.mLastAccessTime,
+                MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read64));
+
+  QM_TRY_UNWRAP(fullOriginMetadata.mPersisted,
+                MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, ReadBoolean));
+
+  QM_TRY_INSPECT(const bool& reservedData1,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read32));
+  Unused << reservedData1;
+
+  // XXX Use for the persistence type.
+  QM_TRY_INSPECT(const bool& reservedData2,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read32));
+  Unused << reservedData2;
+
+  fullOriginMetadata.mPersistenceType = aPersistenceType;
+
+  QM_TRY_UNWRAP(
+      fullOriginMetadata.mSuffix,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, binaryStream, ReadCString));
+
+  QM_TRY_UNWRAP(
+      fullOriginMetadata.mGroup,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, binaryStream, ReadCString));
+
+  QM_TRY_UNWRAP(
+      fullOriginMetadata.mOrigin,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, binaryStream, ReadCString));
+
+  // Currently unused (used to be isApp).
+  QM_TRY_INSPECT(const bool& dummy,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, ReadBoolean));
+  Unused << dummy;
+
+  QM_TRY(MOZ_TO_RESULT(binaryStream->Close()));
+
+  QM_TRY_INSPECT(const bool& groupUpdated,
+                 MaybeUpdateGroupForOrigin(fullOriginMetadata));
+
+  // A workaround for a bug in GetLastModifiedTime implementation which should
+  // have returned the current time instead of INT64_MIN when there were no
+  // suitable files for getting last modified time.
+  QM_TRY_INSPECT(const bool& lastAccessTimeUpdated,
+                 MaybeUpdateLastAccessTimeForOrigin(fullOriginMetadata));
+
+  if (groupUpdated || lastAccessTimeUpdated) {
+    // Only overwriting .metadata-v2 (used to overwrite .metadata too) to reduce
+    // I/O.
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+        *aDirectory, fullOriginMetadata.mLastAccessTime,
+        fullOriginMetadata.mPersisted, fullOriginMetadata)));
+  }
+
+  return fullOriginMetadata;
+}
+
+Result<FullOriginMetadata, nsresult>
+QuotaManager::LoadFullOriginMetadataWithRestore(nsIFile* aDirectory) {
+  // XXX Once the persistence type is stored in the metadata file, this block
+  // for getting the persistence type from the parent directory name can be
+  // removed.
+  nsCOMPtr<nsIFile> parentDir;
+  QM_TRY(MOZ_TO_RESULT(aDirectory->GetParent(getter_AddRefs(parentDir))));
+
+  const auto maybePersistenceType =
+      PersistenceTypeFromFile(*parentDir, fallible);
+  QM_TRY(OkIf(maybePersistenceType.isSome()), Err(NS_ERROR_FAILURE));
+
+  const auto& persistenceType = maybePersistenceType.value();
+
+  QM_TRY_RETURN(QM_OR_ELSE_WARN(
+      // Expression.
+      LoadFullOriginMetadata(aDirectory, persistenceType),
+      // Fallback.
+      ([&aDirectory, &persistenceType,
+        this](const nsresult rv) -> Result<FullOriginMetadata, nsresult> {
+        QM_TRY(MOZ_TO_RESULT(RestoreDirectoryMetadata2(aDirectory)));
+
+        QM_TRY_RETURN(LoadFullOriginMetadata(aDirectory, persistenceType));
+      })));
+}
+
+template <typename OriginFunc>
+nsresult QuotaManager::InitializeRepository(PersistenceType aPersistenceType,
+                                            OriginFunc&& aOriginFunc) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aPersistenceType == PERSISTENCE_TYPE_TEMPORARY ||
+             aPersistenceType == PERSISTENCE_TYPE_DEFAULT);
+
+  QM_TRY_INSPECT(const auto& directory,
+                 QM_NewLocalFile(GetStoragePath(aPersistenceType)));
+
+  QM_TRY_INSPECT(const bool& created, EnsureDirectory(*directory));
+
+  Unused << created;
+
+  // A keeper to defer the return only in Nightly, so that the telemetry data
+  // for whole profile can be collected
+#ifdef NIGHTLY_BUILD
+  nsresult statusKeeper = NS_OK;
+#endif
+
+  const auto statusKeeperFunc = [&](const nsresult rv) {
+    RECORD_IN_NIGHTLY(statusKeeper, rv);
+  };
+
+  struct RenameAndInitInfo {
+    nsCOMPtr<nsIFile> mOriginDirectory;
+    FullOriginMetadata mFullOriginMetadata;
+    int64_t mTimestamp;
+    bool mPersisted;
+  };
+  nsTArray<RenameAndInitInfo> renameAndInitInfos;
+
+  QM_TRY(([&]() -> Result<Ok, nsresult> {
+    QM_TRY(
+        CollectEachFile(
+            *directory,
+            [&](nsCOMPtr<nsIFile>&& childDirectory) -> Result<Ok, nsresult> {
+              if (NS_WARN_IF(IsShuttingDown())) {
+                RETURN_STATUS_OR_RESULT(statusKeeper, NS_ERROR_ABORT);
+              }
+
+              QM_TRY(
+                  ([this, &childDirectory, &renameAndInitInfos,
+                    aPersistenceType, &aOriginFunc]() -> Result<Ok, nsresult> {
+                    QM_TRY_INSPECT(
+                        const auto& leafName,
+                        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                            nsAutoString, childDirectory, GetLeafName));
+
+                    QM_TRY_INSPECT(const auto& dirEntryKind,
+                                   GetDirEntryKind(*childDirectory));
+
+                    switch (dirEntryKind) {
+                      case nsIFileKind::ExistsAsDirectory: {
+                        QM_TRY_UNWRAP(
+                            auto metadata,
+                            LoadFullOriginMetadataWithRestore(childDirectory));
+
+                        MOZ_ASSERT(metadata.mPersistenceType ==
+                                   aPersistenceType);
+
+                        // FIXME(tt): The check for origin name consistency can
+                        // be removed once we have an upgrade to traverse origin
+                        // directories and check through the directory metadata
+                        // files.
+                        const auto originSanitized =
+                            MakeSanitizedOriginCString(metadata.mOrigin);
+
+                        NS_ConvertUTF16toUTF8 utf8LeafName(leafName);
+                        if (!originSanitized.Equals(utf8LeafName)) {
+                          QM_WARNING(
+                              "The name of the origin directory (%s) doesn't "
+                              "match the sanitized origin string (%s) in the "
+                              "metadata file!",
+                              utf8LeafName.get(), originSanitized.get());
+
+                          // If it's the known case, we try to restore the
+                          // origin directory name if it's possible.
+                          if (originSanitized.Equals(utf8LeafName + "."_ns)) {
+                            const int64_t lastAccessTime =
+                                metadata.mLastAccessTime;
+                            const bool persisted = metadata.mPersisted;
+                            renameAndInitInfos.AppendElement(RenameAndInitInfo{
+                                std::move(childDirectory), std::move(metadata),
+                                lastAccessTime, persisted});
+                            break;
+                          }
+
+                          // XXXtt: Try to restore the unknown cases base on the
+                          // content for their metadata files. Note that if the
+                          // restore fails, QM should maintain a list and ensure
+                          // they won't be accessed after initialization.
+                        }
+
+                        QM_TRY(QM_OR_ELSE_WARN_IF(
+                            // Expression.
+                            MOZ_TO_RESULT(InitializeOrigin(
+                                aPersistenceType, metadata,
+                                metadata.mLastAccessTime, metadata.mPersisted,
+                                childDirectory)),
+                            // Predicate.
+                            IsDatabaseCorruptionError,
+                            // Fallback.
+                            ([&childDirectory](
+                                 const nsresult rv) -> Result<Ok, nsresult> {
+                              // If the origin can't be initialized due to
+                              // corruption, this is a permanent
+                              // condition, and we need to remove all data
+                              // for the origin on disk.
+
+                              QM_TRY(
+                                  MOZ_TO_RESULT(childDirectory->Remove(true)));
+
+                              return Ok{};
+                            })));
+
+                        std::forward<OriginFunc>(aOriginFunc)(metadata);
+
+                        break;
+                      }
+
+                      case nsIFileKind::ExistsAsFile:
+                        if (IsOSMetadata(leafName) || IsDotFile(leafName)) {
+                          break;
+                        }
+
+                        // Unknown files during initialization are now allowed.
+                        // Just warn if we find them.
+                        UNKNOWN_FILE_WARNING(leafName);
+                        break;
+
+                      case nsIFileKind::DoesNotExist:
+                        // Ignore files that got removed externally while
+                        // iterating.
+                        break;
+                    }
+
+                    return Ok{};
+                  }()),
+                  OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+              return Ok{};
+            }),
+        OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+    return Ok{};
+  }()));
+
+  for (auto& info : renameAndInitInfos) {
+    QM_TRY(([&]() -> Result<Ok, nsresult> {
+      QM_TRY(([&directory, &info, this, aPersistenceType,
+               &aOriginFunc]() -> Result<Ok, nsresult> {
+               const auto originDirName =
+                   MakeSanitizedOriginString(info.mFullOriginMetadata.mOrigin);
+
+               // Check if targetDirectory exist.
+               QM_TRY_INSPECT(const auto& targetDirectory,
+                              CloneFileAndAppend(*directory, originDirName));
+
+               QM_TRY_INSPECT(const bool& exists, MOZ_TO_RESULT_INVOKE_MEMBER(
+                                                      targetDirectory, Exists));
+
+               if (exists) {
+                 QM_TRY(MOZ_TO_RESULT(info.mOriginDirectory->Remove(true)));
+
+                 return Ok{};
+               }
+
+               QM_TRY(MOZ_TO_RESULT(
+                   info.mOriginDirectory->RenameTo(nullptr, originDirName)));
+
+               // XXX We don't check corruption here ?
+               QM_TRY(MOZ_TO_RESULT(InitializeOrigin(
+                   aPersistenceType, info.mFullOriginMetadata, info.mTimestamp,
+                   info.mPersisted, targetDirectory)));
+
+               std::forward<OriginFunc>(aOriginFunc)(info.mFullOriginMetadata);
+
+               return Ok{};
+             }()),
+             OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+      return Ok{};
+    }()));
+  }
+
+#ifdef NIGHTLY_BUILD
+  if (NS_FAILED(statusKeeper)) {
+    return statusKeeper;
+  }
+#endif
+
+  return NS_OK;
+}
+
+nsresult QuotaManager::InitializeOrigin(PersistenceType aPersistenceType,
+                                        const OriginMetadata& aOriginMetadata,
+                                        int64_t aAccessTime, bool aPersisted,
+                                        nsIFile* aDirectory) {
+  AssertIsOnIOThread();
+
+  const bool trackQuota = aPersistenceType != PERSISTENCE_TYPE_PERSISTENT;
+
+  // We need to initialize directories of all clients if they exists and also
+  // get the total usage to initialize the quota.
+
+  ClientUsageArray clientUsages;
+
+  // A keeper to defer the return only in Nightly, so that the telemetry data
+  // for whole profile can be collected
+#ifdef NIGHTLY_BUILD
+  nsresult statusKeeper = NS_OK;
+#endif
+
+  QM_TRY(([&, statusKeeperFunc = [&](const nsresult rv) {
+            RECORD_IN_NIGHTLY(statusKeeper, rv);
+          }]() -> Result<Ok, nsresult> {
+    QM_TRY(
+        CollectEachFile(
+            *aDirectory,
+            [&](const nsCOMPtr<nsIFile>& file) -> Result<Ok, nsresult> {
+              if (NS_WARN_IF(IsShuttingDown())) {
+                RETURN_STATUS_OR_RESULT(statusKeeper, NS_ERROR_ABORT);
+              }
+
+              QM_TRY(
+                  ([this, &file, trackQuota, aPersistenceType, &aOriginMetadata,
+                    &clientUsages]() -> Result<Ok, nsresult> {
+                    QM_TRY_INSPECT(const auto& leafName,
+                                   MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsAutoString, file, GetLeafName));
+
+                    QM_TRY_INSPECT(const auto& dirEntryKind,
+                                   GetDirEntryKind(*file));
+
+                    switch (dirEntryKind) {
+                      case nsIFileKind::ExistsAsDirectory: {
+                        Client::Type clientType;
+                        const bool ok = Client::TypeFromText(
+                            leafName, clientType, fallible);
+                        if (!ok) {
+                          // Unknown directories during initialization are now
+                          // allowed. Just warn if we find them.
+                          UNKNOWN_FILE_WARNING(leafName);
+                          break;
+                        }
+
+                        if (trackQuota) {
+                          QM_TRY_INSPECT(
+                              const auto& usageInfo,
+                              (*mClients)[clientType]->InitOrigin(
+                                  aPersistenceType, aOriginMetadata,
+                                  /* aCanceled */ Atomic<bool>(false)));
+
+                          MOZ_ASSERT(!clientUsages[clientType]);
+
+                          if (usageInfo.TotalUsage()) {
+                            // XXX(Bug 1683863) Until we identify the root cause
+                            // of seemingly converted-from-negative usage
+                            // values, we will just treat them as unset here,
+                            // but log a warning to the browser console.
+                            if (static_cast<int64_t>(*usageInfo.TotalUsage()) >=
+                                0) {
+                              clientUsages[clientType] = usageInfo.TotalUsage();
+                            } else {
+#if defined(EARLY_BETA_OR_EARLIER) || defined(DEBUG)
+                              const nsCOMPtr<nsIConsoleService> console =
+                                  do_GetService(NS_CONSOLESERVICE_CONTRACTID);
+                              if (console) {
+                                console->LogStringMessage(
+                                    nsString(
+                                        u"QuotaManager warning: client "_ns +
+                                        leafName +
+                                        u" reported negative usage for group "_ns +
+                                        NS_ConvertUTF8toUTF16(
+                                            aOriginMetadata.mGroup) +
+                                        u", origin "_ns +
+                                        NS_ConvertUTF8toUTF16(
+                                            aOriginMetadata.mOrigin))
+                                        .get());
+                              }
+#endif
+                            }
+                          }
+                        } else {
+                          QM_TRY(MOZ_TO_RESULT(
+                              (*mClients)[clientType]
+                                  ->InitOriginWithoutTracking(
+                                      aPersistenceType, aOriginMetadata,
+                                      /* aCanceled */ Atomic<bool>(false))));
+                        }
+
+                        break;
+                      }
+
+                      case nsIFileKind::ExistsAsFile:
+                        if (IsOriginMetadata(leafName)) {
+                          break;
+                        }
+
+                        if (IsTempMetadata(leafName)) {
+                          QM_TRY(MOZ_TO_RESULT(
+                              file->Remove(/* recursive */ false)));
+
+                          break;
+                        }
+
+                        if (IsOSMetadata(leafName) || IsDotFile(leafName)) {
+                          break;
+                        }
+
+                        // Unknown files during initialization are now allowed.
+                        // Just warn if we find them.
+                        UNKNOWN_FILE_WARNING(leafName);
+                        // Bug 1595448 will handle the case for unknown files
+                        // like idb, cache, or ls.
+                        break;
+
+                      case nsIFileKind::DoesNotExist:
+                        // Ignore files that got removed externally while
+                        // iterating.
+                        break;
+                    }
+
+                    return Ok{};
+                  }()),
+                  OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+              return Ok{};
+            }),
+        OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS, statusKeeperFunc);
+
+    return Ok{};
+  }()));
+
+#ifdef NIGHTLY_BUILD
+  if (NS_FAILED(statusKeeper)) {
+    return statusKeeper;
+  }
+#endif
+
+  if (trackQuota) {
+    const auto usage = std::accumulate(
+        clientUsages.cbegin(), clientUsages.cend(), CheckedUint64(0),
+        [](CheckedUint64 value, const Maybe<uint64_t>& clientUsage) {
+          return value + clientUsage.valueOr(0);
+        });
+
+    // XXX Should we log more information, i.e. the whole clientUsages array, in
+    // case usage is not valid?
+
+    QM_TRY(OkIf(usage.isValid()), NS_ERROR_FAILURE);
+
+    InitQuotaForOrigin(
+        FullOriginMetadata{aOriginMetadata, aPersisted, aAccessTime},
+        clientUsages, usage.value());
+  }
+
+  return NS_OK;
+}
+
+nsresult
+QuotaManager::UpgradeFromIndexedDBDirectoryToPersistentStorageDirectory(
+    nsIFile* aIndexedDBDir) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aIndexedDBDir);
+
+  const auto innerFunc = [this, &aIndexedDBDir](const auto&) -> nsresult {
+    bool isDirectory;
+    QM_TRY(MOZ_TO_RESULT(aIndexedDBDir->IsDirectory(&isDirectory)));
+
+    if (!isDirectory) {
+      NS_WARNING("indexedDB entry is not a directory!");
+      return NS_OK;
+    }
+
+    auto persistentStorageDirOrErr = QM_NewLocalFile(*mStoragePath);
+    if (NS_WARN_IF(persistentStorageDirOrErr.isErr())) {
+      return persistentStorageDirOrErr.unwrapErr();
+    }
+
+    nsCOMPtr<nsIFile> persistentStorageDir = persistentStorageDirOrErr.unwrap();
+
+    QM_TRY(MOZ_TO_RESULT(persistentStorageDir->Append(
+        nsLiteralString(PERSISTENT_DIRECTORY_NAME))));
+
+    bool exists;
+    QM_TRY(MOZ_TO_RESULT(persistentStorageDir->Exists(&exists)));
+
+    if (exists) {
+      QM_WARNING("Deleting old <profile>/indexedDB directory!");
+
+      QM_TRY(MOZ_TO_RESULT(aIndexedDBDir->Remove(/* aRecursive */ true)));
+
+      return NS_OK;
+    }
+
+    nsCOMPtr<nsIFile> storageDir;
+    QM_TRY(MOZ_TO_RESULT(
+        persistentStorageDir->GetParent(getter_AddRefs(storageDir))));
+
+    // MoveTo() is atomic if the move happens on the same volume which should
+    // be our case, so even if we crash in the middle of the operation nothing
+    // breaks next time we try to initialize.
+    // However there's a theoretical possibility that the indexedDB directory
+    // is on different volume, but it should be rare enough that we don't have
+    // to worry about it.
+    QM_TRY(MOZ_TO_RESULT(aIndexedDBDir->MoveTo(
+        storageDir, nsLiteralString(PERSISTENT_DIRECTORY_NAME))));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeFromIndexedDBDirectory,
+                               innerFunc);
+}
+
+nsresult
+QuotaManager::UpgradeFromPersistentStorageDirectoryToDefaultStorageDirectory(
+    nsIFile* aPersistentStorageDir) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aPersistentStorageDir);
+
+  const auto innerFunc = [this,
+                          &aPersistentStorageDir](const auto&) -> nsresult {
+    QM_TRY_INSPECT(
+        const bool& isDirectory,
+        MOZ_TO_RESULT_INVOKE_MEMBER(aPersistentStorageDir, IsDirectory));
+
+    if (!isDirectory) {
+      NS_WARNING("persistent entry is not a directory!");
+      return NS_OK;
+    }
+
+    {
+      QM_TRY_INSPECT(const auto& defaultStorageDir,
+                     QM_NewLocalFile(*mDefaultStoragePath));
+
+      QM_TRY_INSPECT(const bool& exists,
+                     MOZ_TO_RESULT_INVOKE_MEMBER(defaultStorageDir, Exists));
+
+      if (exists) {
+        QM_WARNING("Deleting old <profile>/storage/persistent directory!");
+
+        QM_TRY(MOZ_TO_RESULT(
+            aPersistentStorageDir->Remove(/* aRecursive */ true)));
+
+        return NS_OK;
+      }
+    }
+
+    {
+      // Create real metadata files for origin directories in persistent
+      // storage.
+      auto helper = MakeRefPtr<CreateOrUpgradeDirectoryMetadataHelper>(
+          aPersistentStorageDir);
+
+      QM_TRY(MOZ_TO_RESULT(helper->Init()));
+
+      QM_TRY(MOZ_TO_RESULT(helper->ProcessRepository()));
+
+      // Upgrade metadata files for origin directories in temporary storage.
+      QM_TRY_INSPECT(const auto& temporaryStorageDir,
+                     QM_NewLocalFile(*mTemporaryStoragePath));
+
+      QM_TRY_INSPECT(const bool& exists,
+                     MOZ_TO_RESULT_INVOKE_MEMBER(temporaryStorageDir, Exists));
+
+      if (exists) {
+        QM_TRY_INSPECT(
+            const bool& isDirectory,
+            MOZ_TO_RESULT_INVOKE_MEMBER(temporaryStorageDir, IsDirectory));
+
+        if (!isDirectory) {
+          NS_WARNING("temporary entry is not a directory!");
+          return NS_OK;
+        }
+
+        helper = MakeRefPtr<CreateOrUpgradeDirectoryMetadataHelper>(
+            temporaryStorageDir);
+
+        QM_TRY(MOZ_TO_RESULT(helper->Init()));
+
+        QM_TRY(MOZ_TO_RESULT(helper->ProcessRepository()));
+      }
+    }
+
+    // And finally rename persistent to default.
+    QM_TRY(MOZ_TO_RESULT(aPersistentStorageDir->RenameTo(
+        nullptr, nsLiteralString(DEFAULT_DIRECTORY_NAME))));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(
+      Initialization::UpgradeFromPersistentStorageDirectory, innerFunc);
+}
+
+template <typename Helper>
+nsresult QuotaManager::UpgradeStorage(const int32_t aOldVersion,
+                                      const int32_t aNewVersion,
+                                      mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aNewVersion > aOldVersion);
+  MOZ_ASSERT(aNewVersion <= kStorageVersion);
+  MOZ_ASSERT(aConnection);
+
+  for (const PersistenceType persistenceType : kAllPersistenceTypes) {
+    QM_TRY_UNWRAP(auto directory,
+                  QM_NewLocalFile(GetStoragePath(persistenceType)));
+
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists));
+
+    if (!exists) {
+      continue;
+    }
+
+    RefPtr<UpgradeStorageHelperBase> helper = new Helper(directory);
+
+    QM_TRY(MOZ_TO_RESULT(helper->Init()));
+
+    QM_TRY(MOZ_TO_RESULT(helper->ProcessRepository()));
+  }
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const int32_t& storageVersion,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, GetSchemaVersion));
+
+    MOZ_ASSERT(storageVersion == aOldVersion);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(aConnection->SetSchemaVersion(aNewVersion)));
+
+  return NS_OK;
+}
+
+nsresult QuotaManager::UpgradeStorageFrom0_0To1_0(
+    mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  const auto innerFunc = [this, &aConnection](const auto&) -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(UpgradeStorage<UpgradeStorageFrom0_0To1_0Helper>(
+        0, MakeStorageVersion(1, 0), aConnection)));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeStorageFrom0_0To1_0,
+                               innerFunc);
+}
+
+nsresult QuotaManager::UpgradeStorageFrom1_0To2_0(
+    mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  // The upgrade consists of a number of logically distinct bugs that
+  // intentionally got fixed at the same time to trigger just one major
+  // version bump.
+  //
+  //
+  // Morgue directory cleanup
+  // [Feature/Bug]:
+  // The original bug that added "on demand" morgue cleanup is 1165119.
+  //
+  // [Mutations]:
+  // Morgue directories are removed from all origin directories during the
+  // upgrade process. Origin initialization and usage calculation doesn't try
+  // to remove morgue directories anymore.
+  //
+  // [Downgrade-incompatible changes]:
+  // Morgue directories can reappear if user runs an already upgraded profile
+  // in an older version of Firefox. Morgue directories then prevent current
+  // Firefox from initializing and using the storage.
+  //
+  //
+  // App data removal
+  // [Feature/Bug]:
+  // The bug that removes isApp flags is 1311057.
+  //
+  // [Mutations]:
+  // Origin directories with appIds are removed during the upgrade process.
+  //
+  // [Downgrade-incompatible changes]:
+  // Origin directories with appIds can reappear if user runs an already
+  // upgraded profile in an older version of Firefox. Origin directories with
+  // appIds don't prevent current Firefox from initializing and using the
+  // storage, but they wouldn't ever be removed again, potentially causing
+  // problems once appId is removed from origin attributes.
+  //
+  //
+  // Strip obsolete origin attributes
+  // [Feature/Bug]:
+  // The bug that strips obsolete origin attributes is 1314361.
+  //
+  // [Mutations]:
+  // Origin directories with obsolete origin attributes are renamed and their
+  // metadata files are updated during the upgrade process.
+  //
+  // [Downgrade-incompatible changes]:
+  // Origin directories with obsolete origin attributes can reappear if user
+  // runs an already upgraded profile in an older version of Firefox. Origin
+  // directories with obsolete origin attributes don't prevent current Firefox
+  // from initializing and using the storage, but they wouldn't ever be upgraded
+  // again, potentially causing problems in future.
+  //
+  //
+  // File manager directory renaming (client specific)
+  // [Feature/Bug]:
+  // The original bug that added "on demand" file manager directory renaming is
+  // 1056939.
+  //
+  // [Mutations]:
+  // All file manager directories are renamed to contain the ".files" suffix.
+  //
+  // [Downgrade-incompatible changes]:
+  // File manager directories with the ".files" suffix prevent older versions of
+  // Firefox from initializing and using the storage.
+  // File manager directories without the ".files" suffix can appear if user
+  // runs an already upgraded profile in an older version of Firefox. File
+  // manager directories without the ".files" suffix then prevent current
+  // Firefox from initializing and using the storage.
+
+  const auto innerFunc = [this, &aConnection](const auto&) -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(UpgradeStorage<UpgradeStorageFrom1_0To2_0Helper>(
+        MakeStorageVersion(1, 0), MakeStorageVersion(2, 0), aConnection)));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeStorageFrom1_0To2_0,
+                               innerFunc);
+}
+
+nsresult QuotaManager::UpgradeStorageFrom2_0To2_1(
+    mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  // The upgrade is mainly to create a directory padding file in DOM Cache
+  // directory to record the overall padding size of an origin.
+
+  const auto innerFunc = [this, &aConnection](const auto&) -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(UpgradeStorage<UpgradeStorageFrom2_0To2_1Helper>(
+        MakeStorageVersion(2, 0), MakeStorageVersion(2, 1), aConnection)));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeStorageFrom2_0To2_1,
+                               innerFunc);
+}
+
+nsresult QuotaManager::UpgradeStorageFrom2_1To2_2(
+    mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  // The upgrade is mainly to clean obsolete origins in the repositoies, remove
+  // asmjs client, and ".tmp" file in the idb folers.
+
+  const auto innerFunc = [this, &aConnection](const auto&) -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(UpgradeStorage<UpgradeStorageFrom2_1To2_2Helper>(
+        MakeStorageVersion(2, 1), MakeStorageVersion(2, 2), aConnection)));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeStorageFrom2_1To2_2,
+                               innerFunc);
+}
+
+nsresult QuotaManager::UpgradeStorageFrom2_2To2_3(
+    mozIStorageConnection* aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aConnection);
+
+  const auto innerFunc = [&aConnection](const auto&) -> nsresult {
+    // Table `database`
+    QM_TRY(MOZ_TO_RESULT(aConnection->ExecuteSimpleSQL(
+        nsLiteralCString("CREATE TABLE database"
+                         "( cache_version INTEGER NOT NULL DEFAULT 0"
+                         ");"))));
+
+    QM_TRY(MOZ_TO_RESULT(aConnection->ExecuteSimpleSQL(
+        nsLiteralCString("INSERT INTO database (cache_version) "
+                         "VALUES (0)"))));
+
+#ifdef DEBUG
+    {
+      QM_TRY_INSPECT(
+          const int32_t& storageVersion,
+          MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, GetSchemaVersion));
+
+      MOZ_ASSERT(storageVersion == MakeStorageVersion(2, 2));
+    }
+#endif
+
+    QM_TRY(
+        MOZ_TO_RESULT(aConnection->SetSchemaVersion(MakeStorageVersion(2, 3))));
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(Initialization::UpgradeStorageFrom2_2To2_3,
+                               innerFunc);
+}
+
+nsresult QuotaManager::MaybeRemoveLocalStorageDataAndArchive(
+    nsIFile& aLsArchiveFile) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!CachedNextGenLocalStorageEnabled());
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+
+  if (!exists) {
+    // If the ls archive doesn't exist then ls directories can't exist either.
+    return NS_OK;
+  }
+
+  QM_TRY(MOZ_TO_RESULT(MaybeRemoveLocalStorageDirectories()));
+
+  InvalidateQuotaCache();
+
+  // Finally remove the ls archive, so we don't have to check all origin
+  // directories next time this method is called.
+  QM_TRY(MOZ_TO_RESULT(aLsArchiveFile.Remove(false)));
+
+  return NS_OK;
+}
+
+nsresult QuotaManager::MaybeRemoveLocalStorageDirectories() {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& defaultStorageDir,
+                 QM_NewLocalFile(*mDefaultStoragePath));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(defaultStorageDir, Exists));
+
+  if (!exists) {
+    return NS_OK;
+  }
+
+  QM_TRY(CollectEachFile(
+      *defaultStorageDir,
+      [](const nsCOMPtr<nsIFile>& originDir) -> Result<Ok, nsresult> {
+#ifdef DEBUG
+        {
+          QM_TRY_INSPECT(const bool& exists,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(originDir, Exists));
+          MOZ_ASSERT(exists);
+        }
+#endif
+
+        QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*originDir));
+
+        switch (dirEntryKind) {
+          case nsIFileKind::ExistsAsDirectory: {
+            QM_TRY_INSPECT(
+                const auto& lsDir,
+                CloneFileAndAppend(*originDir, NS_LITERAL_STRING_FROM_CSTRING(
+                                                   LS_DIRECTORY_NAME)));
+
+            {
+              QM_TRY_INSPECT(const bool& exists,
+                             MOZ_TO_RESULT_INVOKE_MEMBER(lsDir, Exists));
+
+              if (!exists) {
+                return Ok{};
+              }
+            }
+
+            {
+              QM_TRY_INSPECT(const bool& isDirectory,
+                             MOZ_TO_RESULT_INVOKE_MEMBER(lsDir, IsDirectory));
+
+              if (!isDirectory) {
+                QM_WARNING("ls entry is not a directory!");
+
+                return Ok{};
+              }
+            }
+
+            nsString path;
+            QM_TRY(MOZ_TO_RESULT(lsDir->GetPath(path)));
+
+            QM_WARNING("Deleting %s directory!",
+                       NS_ConvertUTF16toUTF8(path).get());
+
+            QM_TRY(MOZ_TO_RESULT(lsDir->Remove(/* aRecursive */ true)));
+
+            break;
+          }
+
+          case nsIFileKind::ExistsAsFile: {
+            QM_TRY_INSPECT(const auto& leafName,
+                           MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                               nsAutoString, originDir, GetLeafName));
+
+            // Unknown files during upgrade are allowed. Just warn if we find
+            // them.
+            if (!IsOSMetadata(leafName)) {
+              UNKNOWN_FILE_WARNING(leafName);
+            }
+
+            break;
+          }
+
+          case nsIFileKind::DoesNotExist:
+            // Ignore files that got removed externally while iterating.
+            break;
+        }
+        return Ok{};
+      }));
+
+  return NS_OK;
+}
+
+Result<Ok, nsresult> QuotaManager::CopyLocalStorageArchiveFromWebAppsStore(
+    nsIFile& aLsArchiveFile) const {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+    MOZ_ASSERT(!exists);
+  }
+#endif
+
+  // Get the storage service first, we will need it at multiple places.
+  QM_TRY_INSPECT(const auto& ss,
+                 MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<mozIStorageService>,
+                                         MOZ_SELECT_OVERLOAD(do_GetService),
+                                         MOZ_STORAGE_SERVICE_CONTRACTID));
+
+  // Get the web apps store file.
+  QM_TRY_INSPECT(const auto& webAppsStoreFile, QM_NewLocalFile(mBasePath));
+
+  QM_TRY(MOZ_TO_RESULT(
+      webAppsStoreFile->Append(nsLiteralString(WEB_APPS_STORE_FILE_NAME))));
+
+  // Now check if the web apps store is useable.
+  QM_TRY_INSPECT(const auto& connection,
+                 CreateWebAppsStoreConnection(*webAppsStoreFile, *ss));
+
+  if (connection) {
+    // Find out the journal mode.
+    QM_TRY_INSPECT(const auto& stmt,
+                   CreateAndExecuteSingleStepStatement(
+                       *connection, "PRAGMA journal_mode;"_ns));
+
+    QM_TRY_INSPECT(const auto& journalMode,
+                   MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoCString, *stmt,
+                                                     GetUTF8String, 0));
+
+    QM_TRY(MOZ_TO_RESULT(stmt->Finalize()));
+
+    if (journalMode.EqualsLiteral("wal")) {
+      // We don't copy the WAL file, so make sure the old database is fully
+      // checkpointed.
+      QM_TRY(MOZ_TO_RESULT(
+          connection->ExecuteSimpleSQL("PRAGMA wal_checkpoint(TRUNCATE);"_ns)));
+    }
+
+    // Explicitely close the connection before the old database is copied.
+    QM_TRY(MOZ_TO_RESULT(connection->Close()));
+
+    // Copy the old database. The database is copied from
+    // <profile>/webappsstore.sqlite to
+    // <profile>/storage/ls-archive-tmp.sqlite
+    // We use a "-tmp" postfix since we are not done yet.
+    QM_TRY_INSPECT(const auto& storageDir, QM_NewLocalFile(*mStoragePath));
+
+    QM_TRY(MOZ_TO_RESULT(webAppsStoreFile->CopyTo(
+        storageDir, nsLiteralString(LS_ARCHIVE_TMP_FILE_NAME))));
+
+    QM_TRY_INSPECT(const auto& lsArchiveTmpFile,
+                   GetLocalStorageArchiveTmpFile(*mStoragePath));
+
+    if (journalMode.EqualsLiteral("wal")) {
+      QM_TRY_INSPECT(
+          const auto& lsArchiveTmpConnection,
+          MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+              nsCOMPtr<mozIStorageConnection>, ss, OpenUnsharedDatabase,
+              lsArchiveTmpFile, mozIStorageService::CONNECTION_DEFAULT));
+
+      // The archive will only be used for lazy data migration. There won't be
+      // any concurrent readers and writers that could benefit from Write-Ahead
+      // Logging. So switch to a standard rollback journal. The standard
+      // rollback journal also provides atomicity across multiple attached
+      // databases which is import for the lazy data migration to work safely.
+      QM_TRY(MOZ_TO_RESULT(lsArchiveTmpConnection->ExecuteSimpleSQL(
+          "PRAGMA journal_mode = DELETE;"_ns)));
+
+      // Close the connection explicitly. We are going to rename the file below.
+      QM_TRY(MOZ_TO_RESULT(lsArchiveTmpConnection->Close()));
+    }
+
+    // Finally, rename ls-archive-tmp.sqlite to ls-archive.sqlite
+    QM_TRY(MOZ_TO_RESULT(lsArchiveTmpFile->MoveTo(
+        nullptr, nsLiteralString(LS_ARCHIVE_FILE_NAME))));
+
+    return Ok{};
+  }
+
+  // If webappsstore database is not useable, just create an empty archive.
+  // XXX The code below should be removed and the caller should call us only
+  // when webappstore.sqlite exists. CreateWebAppsStoreConnection should be
+  // reworked to propagate database corruption instead of returning null
+  // connection.
+  // So, if there's no webappsstore.sqlite
+  // MaybeCreateOrUpgradeLocalStorageArchive will call
+  // CreateEmptyLocalStorageArchive instead of
+  // CopyLocalStorageArchiveFromWebAppsStore.
+  // If there's any corruption detected during
+  // MaybeCreateOrUpgradeLocalStorageArchive (including nested calls like
+  // CopyLocalStorageArchiveFromWebAppsStore and CreateWebAppsStoreConnection)
+  // EnsureStorageIsInitialized will fallback to
+  // CreateEmptyLocalStorageArchive.
+
+  // Ensure the storage directory actually exists.
+  QM_TRY_INSPECT(const auto& storageDirectory, QM_NewLocalFile(*mStoragePath));
+
+  QM_TRY_INSPECT(const bool& created, EnsureDirectory(*storageDirectory));
+
+  Unused << created;
+
+  QM_TRY_UNWRAP(auto lsArchiveConnection,
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                    nsCOMPtr<mozIStorageConnection>, ss, OpenUnsharedDatabase,
+                    &aLsArchiveFile, mozIStorageService::CONNECTION_DEFAULT));
+
+  QM_TRY(MOZ_TO_RESULT(
+      StorageDBUpdater::CreateCurrentSchema(lsArchiveConnection)));
+
+  return Ok{};
+}
+
+Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+QuotaManager::CreateLocalStorageArchiveConnection(
+    nsIFile& aLsArchiveFile) const {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+    MOZ_ASSERT(exists);
+  }
+#endif
+
+  QM_TRY_INSPECT(const bool& isDirectory,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, IsDirectory));
+
+  // A directory with the name of the archive file is treated as corruption
+  // (similarly as wrong content of the file).
+  QM_TRY(OkIf(!isDirectory), Err(NS_ERROR_FILE_CORRUPTED));
+
+  QM_TRY_INSPECT(const auto& ss,
+                 MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<mozIStorageService>,
+                                         MOZ_SELECT_OVERLOAD(do_GetService),
+                                         MOZ_STORAGE_SERVICE_CONTRACTID));
+
+  // This may return NS_ERROR_FILE_CORRUPTED too.
+  QM_TRY_UNWRAP(auto connection,
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                    nsCOMPtr<mozIStorageConnection>, ss, OpenUnsharedDatabase,
+                    &aLsArchiveFile, mozIStorageService::CONNECTION_DEFAULT));
+
+  // The legacy LS implementation removes the database and creates an empty one
+  // when the schema can't be updated. The same effect can be achieved here by
+  // mapping all errors to NS_ERROR_FILE_CORRUPTED. One such case is tested by
+  // sub test case 3 of dom/localstorage/test/unit/test_archive.js
+  QM_TRY(
+      MOZ_TO_RESULT(StorageDBUpdater::Update(connection))
+          .mapErr([](const nsresult rv) { return NS_ERROR_FILE_CORRUPTED; }));
+
+  return connection;
+}
+
+Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+QuotaManager::RecopyLocalStorageArchiveFromWebAppsStore(
+    nsIFile& aLsArchiveFile) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+  QM_TRY(MOZ_TO_RESULT(MaybeRemoveLocalStorageDirectories()));
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+
+    MOZ_ASSERT(exists);
+  }
+#endif
+
+  QM_TRY(MOZ_TO_RESULT(aLsArchiveFile.Remove(false)));
+
+  QM_TRY(CopyLocalStorageArchiveFromWebAppsStore(aLsArchiveFile));
+
+  QM_TRY_UNWRAP(auto connection,
+                CreateLocalStorageArchiveConnection(aLsArchiveFile));
+
+  QM_TRY(MOZ_TO_RESULT(InitializeLocalStorageArchive(connection)));
+
+  return connection;
+}
+
+Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+QuotaManager::DowngradeLocalStorageArchive(nsIFile& aLsArchiveFile) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+  QM_TRY_UNWRAP(auto connection,
+                RecopyLocalStorageArchiveFromWebAppsStore(aLsArchiveFile));
+
+  QM_TRY(MOZ_TO_RESULT(
+      SaveLocalStorageArchiveVersion(connection, kLocalStorageArchiveVersion)));
+
+  return connection;
+}
+
+Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+QuotaManager::UpgradeLocalStorageArchiveFromLessThan4To4(
+    nsIFile& aLsArchiveFile) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+  QM_TRY_UNWRAP(auto connection,
+                RecopyLocalStorageArchiveFromWebAppsStore(aLsArchiveFile));
+
+  QM_TRY(MOZ_TO_RESULT(SaveLocalStorageArchiveVersion(connection, 4)));
+
+  return connection;
+}
+
+/*
+nsresult QuotaManager::UpgradeLocalStorageArchiveFrom4To5(
+    nsCOMPtr<mozIStorageConnection>& aConnection) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(CachedNextGenLocalStorageEnabled());
+
+  nsresult rv = SaveLocalStorageArchiveVersion(aConnection, 5);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+*/
+
+#ifdef DEBUG
+
+void QuotaManager::AssertStorageIsInitialized() const {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(IsStorageInitialized());
+}
+
+#endif  // DEBUG
+
+nsresult QuotaManager::MaybeUpgradeToDefaultStorageDirectory(
+    nsIFile& aStorageFile) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& storageFileExists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aStorageFile, Exists));
+
+  if (!storageFileExists) {
+    QM_TRY_INSPECT(const auto& indexedDBDir, QM_NewLocalFile(*mIndexedDBPath));
+
+    QM_TRY_INSPECT(const auto& indexedDBDirExists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(indexedDBDir, Exists));
+
+    if (indexedDBDirExists) {
+      QM_TRY(MOZ_TO_RESULT(
+          UpgradeFromIndexedDBDirectoryToPersistentStorageDirectory(
+              indexedDBDir)));
+    }
+
+    QM_TRY_INSPECT(const auto& persistentStorageDir,
+                   QM_NewLocalFile(*mStoragePath));
+
+    QM_TRY(MOZ_TO_RESULT(persistentStorageDir->Append(
+        nsLiteralString(PERSISTENT_DIRECTORY_NAME))));
+
+    QM_TRY_INSPECT(const auto& persistentStorageDirExists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(persistentStorageDir, Exists));
+
+    if (persistentStorageDirExists) {
+      QM_TRY(MOZ_TO_RESULT(
+          UpgradeFromPersistentStorageDirectoryToDefaultStorageDirectory(
+              persistentStorageDir)));
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult QuotaManager::MaybeCreateOrUpgradeStorage(
+    mozIStorageConnection& aConnection) {
+  AssertIsOnIOThread();
+
+  QM_TRY_UNWRAP(auto storageVersion,
+                MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, GetSchemaVersion));
+
+  // Hacky downgrade logic!
+  // If we see major.minor of 3.0, downgrade it to be 2.1.
+  if (storageVersion == kHackyPreDowngradeStorageVersion) {
+    storageVersion = kHackyPostDowngradeStorageVersion;
+    QM_TRY(MOZ_TO_RESULT(aConnection.SetSchemaVersion(storageVersion)),
+           QM_PROPAGATE,
+           [](const auto&) { MOZ_ASSERT(false, "Downgrade didn't take."); });
+  }
+
+  QM_TRY(OkIf(GetMajorStorageVersion(storageVersion) <= kMajorStorageVersion),
+         NS_ERROR_FAILURE, [](const auto&) {
+           NS_WARNING("Unable to initialize storage, version is too high!");
+         });
+
+  if (storageVersion < kStorageVersion) {
+    const bool newDatabase = !storageVersion;
+
+    QM_TRY_INSPECT(const auto& storageDir, QM_NewLocalFile(*mStoragePath));
+
+    QM_TRY_INSPECT(const auto& storageDirExists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(storageDir, Exists));
+
+    const bool newDirectory = !storageDirExists;
+
+    if (newDatabase) {
+      // Set the page size first.
+      if (kSQLitePageSizeOverride) {
+        QM_TRY(MOZ_TO_RESULT(aConnection.ExecuteSimpleSQL(nsPrintfCString(
+            "PRAGMA page_size = %" PRIu32 ";", kSQLitePageSizeOverride))));
+      }
+    }
+
+    mozStorageTransaction transaction(
+        &aConnection, false, mozIStorageConnection::TRANSACTION_IMMEDIATE);
+
+    QM_TRY(MOZ_TO_RESULT(transaction.Start()));
+
+    // An upgrade method can upgrade the database, the storage or both.
+    // The upgrade loop below can only be avoided when there's no database and
+    // no storage yet (e.g. new profile).
+    if (newDatabase && newDirectory) {
+      QM_TRY(MOZ_TO_RESULT(CreateTables(&aConnection)));
+
+#ifdef DEBUG
+      {
+        QM_TRY_INSPECT(
+            const int32_t& storageVersion,
+            MOZ_TO_RESULT_INVOKE_MEMBER(aConnection, GetSchemaVersion),
+            QM_ASSERT_UNREACHABLE);
+        MOZ_ASSERT(storageVersion == kStorageVersion);
+      }
+#endif
+
+      QM_TRY(MOZ_TO_RESULT(aConnection.ExecuteSimpleSQL(
+          nsLiteralCString("INSERT INTO database (cache_version) "
+                           "VALUES (0)"))));
+    } else {
+      // This logic needs to change next time we change the storage!
+      static_assert(kStorageVersion == int32_t((2 << 16) + 3),
+                    "Upgrade function needed due to storage version increase.");
+
+      while (storageVersion != kStorageVersion) {
+        if (storageVersion == 0) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeStorageFrom0_0To1_0(&aConnection)));
+        } else if (storageVersion == MakeStorageVersion(1, 0)) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeStorageFrom1_0To2_0(&aConnection)));
+        } else if (storageVersion == MakeStorageVersion(2, 0)) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeStorageFrom2_0To2_1(&aConnection)));
+        } else if (storageVersion == MakeStorageVersion(2, 1)) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeStorageFrom2_1To2_2(&aConnection)));
+        } else if (storageVersion == MakeStorageVersion(2, 2)) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeStorageFrom2_2To2_3(&aConnection)));
+        } else {
+          QM_FAIL(NS_ERROR_FAILURE, []() {
+            NS_WARNING(
+                "Unable to initialize storage, no upgrade path is "
+                "available!");
+          });
+        }
+
+        QM_TRY_UNWRAP(storageVersion, MOZ_TO_RESULT_INVOKE_MEMBER(
+                                          aConnection, GetSchemaVersion));
+      }
+
+      MOZ_ASSERT(storageVersion == kStorageVersion);
+    }
+
+    QM_TRY(MOZ_TO_RESULT(transaction.Commit()));
+  }
+
+  return NS_OK;
+}
+
+OkOrErr QuotaManager::MaybeRemoveLocalStorageArchiveTmpFile() {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(
+      const auto& lsArchiveTmpFile,
+      QM_TO_RESULT_TRANSFORM(GetLocalStorageArchiveTmpFile(*mStoragePath)));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 QM_TO_RESULT_INVOKE_MEMBER(lsArchiveTmpFile, Exists));
+
+  if (exists) {
+    QM_TRY(QM_TO_RESULT(lsArchiveTmpFile->Remove(false)));
+  }
+
+  return Ok{};
+}
+
+Result<Ok, nsresult> QuotaManager::MaybeCreateOrUpgradeLocalStorageArchive(
+    nsIFile& aLsArchiveFile) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(
+      const bool& lsArchiveFileExisted,
+      ([this, &aLsArchiveFile]() -> Result<bool, nsresult> {
+        QM_TRY_INSPECT(const bool& exists,
+                       MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+
+        if (!exists) {
+          QM_TRY(CopyLocalStorageArchiveFromWebAppsStore(aLsArchiveFile));
+        }
+
+        return exists;
+      }()));
+
+  QM_TRY_UNWRAP(auto connection,
+                CreateLocalStorageArchiveConnection(aLsArchiveFile));
+
+  QM_TRY_INSPECT(const auto& initialized,
+                 IsLocalStorageArchiveInitialized(*connection));
+
+  if (!initialized) {
+    QM_TRY(MOZ_TO_RESULT(InitializeLocalStorageArchive(connection)));
+  }
+
+  QM_TRY_UNWRAP(int32_t version, LoadLocalStorageArchiveVersion(*connection));
+
+  if (version > kLocalStorageArchiveVersion) {
+    // Close local storage archive connection. We are going to remove underlying
+    // file.
+    QM_TRY(MOZ_TO_RESULT(connection->Close()));
+
+    // This will wipe the archive and any migrated data and recopy the archive
+    // from webappsstore.sqlite.
+    QM_TRY_UNWRAP(connection, DowngradeLocalStorageArchive(aLsArchiveFile));
+
+    QM_TRY_UNWRAP(version, LoadLocalStorageArchiveVersion(*connection));
+
+    MOZ_ASSERT(version == kLocalStorageArchiveVersion);
+  } else if (version != kLocalStorageArchiveVersion) {
+    // The version can be zero either when the archive didn't exist or it did
+    // exist, but the archive was created without any version information.
+    // We don't need to do any upgrades only if it didn't exist because existing
+    // archives without version information must be recopied to really fix bug
+    // 1542104. See also bug 1546305 which introduced archive versions.
+    if (!lsArchiveFileExisted) {
+      MOZ_ASSERT(version == 0);
+
+      QM_TRY(MOZ_TO_RESULT(SaveLocalStorageArchiveVersion(
+          connection, kLocalStorageArchiveVersion)));
+    } else {
+      static_assert(kLocalStorageArchiveVersion == 4,
+                    "Upgrade function needed due to LocalStorage archive "
+                    "version increase.");
+
+      while (version != kLocalStorageArchiveVersion) {
+        if (version < 4) {
+          // Close local storage archive connection. We are going to remove
+          // underlying file.
+          QM_TRY(MOZ_TO_RESULT(connection->Close()));
+
+          // This won't do an "upgrade" in a normal sense. It will wipe the
+          // archive and any migrated data and recopy the archive from
+          // webappsstore.sqlite
+          QM_TRY_UNWRAP(connection, UpgradeLocalStorageArchiveFromLessThan4To4(
+                                        aLsArchiveFile));
+        } /* else if (version == 4) {
+          QM_TRY(MOZ_TO_RESULT(UpgradeLocalStorageArchiveFrom4To5(connection)));
+        } */
+        else {
+          QM_FAIL(Err(NS_ERROR_FAILURE), []() {
+            QM_WARNING(
+                "Unable to initialize LocalStorage archive, no upgrade path "
+                "is available!");
+          });
+        }
+
+        QM_TRY_UNWRAP(version, LoadLocalStorageArchiveVersion(*connection));
+      }
+
+      MOZ_ASSERT(version == kLocalStorageArchiveVersion);
+    }
+  }
+
+  // At this point, we have finished initializing the local storage archive, and
+  // can continue storage initialization. We don't know though if the actual
+  // data in the archive file is readable. We can't do a PRAGMA integrity_check
+  // here though, because that would be too heavyweight.
+
+  return Ok{};
+}
+
+Result<Ok, nsresult> QuotaManager::CreateEmptyLocalStorageArchive(
+    nsIFile& aLsArchiveFile) const {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aLsArchiveFile, Exists));
+
+  // If it exists, remove it. It might be a directory, so remove it recursively.
+  if (exists) {
+    QM_TRY(MOZ_TO_RESULT(aLsArchiveFile.Remove(true)));
+
+    // XXX If we crash right here, the next session will copy the archive from
+    // webappsstore.sqlite again!
+    // XXX Create a marker file before removing the archive which can be
+    // used in MaybeCreateOrUpgradeLocalStorageArchive to create an empty
+    // archive instead of recopying it from webapppstore.sqlite (in other
+    // words, finishing what was started here).
+  }
+
+  QM_TRY_INSPECT(const auto& ss,
+                 MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<mozIStorageService>,
+                                         MOZ_SELECT_OVERLOAD(do_GetService),
+                                         MOZ_STORAGE_SERVICE_CONTRACTID));
+
+  QM_TRY_UNWRAP(const auto connection,
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                    nsCOMPtr<mozIStorageConnection>, ss, OpenUnsharedDatabase,
+                    &aLsArchiveFile, mozIStorageService::CONNECTION_DEFAULT));
+
+  QM_TRY(MOZ_TO_RESULT(StorageDBUpdater::CreateCurrentSchema(connection)));
+
+  QM_TRY(MOZ_TO_RESULT(InitializeLocalStorageArchive(connection)));
+
+  QM_TRY(MOZ_TO_RESULT(
+      SaveLocalStorageArchiveVersion(connection, kLocalStorageArchiveVersion)));
+
+  return Ok{};
+}
+
+nsresult QuotaManager::EnsureStorageIsInitialized() {
+  DiagnosticAssertIsOnIOThread();
+
+  const auto innerFunc =
+      [&](const auto& firstInitializationAttempt) -> nsresult {
+    if (mStorageConnection) {
+      MOZ_ASSERT(firstInitializationAttempt.Recorded());
+      return NS_OK;
+    }
+
+    QM_TRY_INSPECT(const auto& storageFile, QM_NewLocalFile(mBasePath));
+    QM_TRY(MOZ_TO_RESULT(storageFile->Append(mStorageName + kSQLiteSuffix)));
+
+    QM_TRY(MOZ_TO_RESULT(MaybeUpgradeToDefaultStorageDirectory(*storageFile)));
+
+    QM_TRY_INSPECT(const auto& ss,
+                   MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<mozIStorageService>,
+                                           MOZ_SELECT_OVERLOAD(do_GetService),
+                                           MOZ_STORAGE_SERVICE_CONTRACTID));
+
+    QM_TRY_UNWRAP(
+        auto connection,
+        QM_OR_ELSE_WARN_IF(
+            // Expression.
+            MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                nsCOMPtr<mozIStorageConnection>, ss, OpenUnsharedDatabase,
+                storageFile, mozIStorageService::CONNECTION_DEFAULT),
+            // Predicate.
+            IsDatabaseCorruptionError,
+            // Fallback.
+            ErrToDefaultOk<nsCOMPtr<mozIStorageConnection>>));
+
+    if (!connection) {
+      // Nuke the database file.
+      QM_TRY(MOZ_TO_RESULT(storageFile->Remove(false)));
+
+      QM_TRY_UNWRAP(connection, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                    nsCOMPtr<mozIStorageConnection>, ss,
+                                    OpenUnsharedDatabase, storageFile,
+                                    mozIStorageService::CONNECTION_DEFAULT));
+    }
+
+    // We want extra durability for this important file.
+    QM_TRY(MOZ_TO_RESULT(
+        connection->ExecuteSimpleSQL("PRAGMA synchronous = EXTRA;"_ns)));
+
+    // Check to make sure that the storage version is correct.
+    QM_TRY(MOZ_TO_RESULT(MaybeCreateOrUpgradeStorage(*connection)));
+
+    QM_TRY(MaybeRemoveLocalStorageArchiveTmpFile());
+
+    QM_TRY_INSPECT(const auto& lsArchiveFile,
+                   GetLocalStorageArchiveFile(*mStoragePath));
+
+    if (CachedNextGenLocalStorageEnabled()) {
+      QM_TRY(QM_OR_ELSE_WARN_IF(
+          // Expression.
+          MaybeCreateOrUpgradeLocalStorageArchive(*lsArchiveFile),
+          // Predicate.
+          IsDatabaseCorruptionError,
+          // Fallback.
+          ([&](const nsresult rv) -> Result<Ok, nsresult> {
+            QM_TRY_RETURN(CreateEmptyLocalStorageArchive(*lsArchiveFile));
+          })));
+    } else {
+      QM_TRY(
+          MOZ_TO_RESULT(MaybeRemoveLocalStorageDataAndArchive(*lsArchiveFile)));
+    }
+
+    QM_TRY_UNWRAP(mCacheUsable, MaybeCreateOrUpgradeCache(*connection));
+
+    if (mCacheUsable && gInvalidateQuotaCache) {
+      QM_TRY(InvalidateCache(*connection));
+
+      gInvalidateQuotaCache = false;
+    }
+
+    mStorageConnection = std::move(connection);
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(
+      Initialization::Storage,
+      "dom::quota::FirstInitializationAttempt::Storage"_ns, innerFunc);
+}
+
+RefPtr<ClientDirectoryLock> QuotaManager::CreateDirectoryLock(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+    Client::Type aClientType, bool aExclusive) {
+  AssertIsOnOwningThread();
+
+  return DirectoryLockImpl::Create(WrapNotNullUnchecked(this), aPersistenceType,
+                                   aOriginMetadata, aClientType, aExclusive);
+}
+
+RefPtr<UniversalDirectoryLock> QuotaManager::CreateDirectoryLockInternal(
+    const Nullable<PersistenceType>& aPersistenceType,
+    const OriginScope& aOriginScope, const Nullable<Client::Type>& aClientType,
+    bool aExclusive) {
+  AssertIsOnOwningThread();
+
+  return DirectoryLockImpl::CreateInternal(WrapNotNullUnchecked(this),
+                                           aPersistenceType, aOriginScope,
+                                           aClientType, aExclusive);
+}
+
+Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult>
+QuotaManager::EnsurePersistentOriginIsInitialized(
+    const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aOriginMetadata.mPersistenceType == PERSISTENCE_TYPE_PERSISTENT);
+  MOZ_DIAGNOSTIC_ASSERT(mStorageConnection);
+
+  const auto innerFunc = [&aOriginMetadata,
+                          this](const auto& firstInitializationAttempt)
+      -> mozilla::Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult> {
+    QM_TRY_UNWRAP(auto directory,
+                  GetDirectoryForOrigin(PERSISTENCE_TYPE_PERSISTENT,
+                                        aOriginMetadata.mOrigin));
+
+    if (mInitializedOrigins.Contains(aOriginMetadata.mOrigin)) {
+      MOZ_ASSERT(firstInitializationAttempt.Recorded());
+      return std::pair(std::move(directory), false);
+    }
+
+    QM_TRY_INSPECT(const bool& created, EnsureOriginDirectory(*directory));
+
+    QM_TRY_INSPECT(
+        const int64_t& timestamp,
+        ([this, created, &directory,
+          &aOriginMetadata]() -> Result<int64_t, nsresult> {
+          if (created) {
+            const int64_t timestamp = PR_Now();
+
+            // Only creating .metadata-v2 to reduce IO.
+            QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(*directory, timestamp,
+                                                          /* aPersisted */ true,
+                                                          aOriginMetadata)));
+
+            return timestamp;
+          }
+
+          // Get the metadata. We only use the timestamp.
+          QM_TRY_INSPECT(const auto& metadata,
+                         LoadFullOriginMetadataWithRestore(directory));
+
+          MOZ_ASSERT(metadata.mLastAccessTime <= PR_Now());
+
+          return metadata.mLastAccessTime;
+        }()));
+
+    QM_TRY(MOZ_TO_RESULT(InitializeOrigin(PERSISTENCE_TYPE_PERSISTENT,
+                                          aOriginMetadata, timestamp,
+                                          /* aPersisted */ true, directory)));
+
+    mInitializedOrigins.AppendElement(aOriginMetadata.mOrigin);
+
+    return std::pair(std::move(directory), created);
+  };
+
+  return ExecuteOriginInitialization(
+      aOriginMetadata.mOrigin, OriginInitialization::PersistentOrigin,
+      "dom::quota::FirstOriginInitializationAttempt::PersistentOrigin"_ns,
+      innerFunc);
+}
+
+Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult>
+QuotaManager::EnsureTemporaryOriginIsInitialized(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+  MOZ_DIAGNOSTIC_ASSERT(mStorageConnection);
+  MOZ_DIAGNOSTIC_ASSERT(mTemporaryStorageInitialized);
+
+  const auto innerFunc = [&aPersistenceType, &aOriginMetadata,
+                          this](const auto&)
+      -> mozilla::Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult> {
+    // Get directory for this origin and persistence type.
+    QM_TRY_UNWRAP(
+        auto directory,
+        GetDirectoryForOrigin(aPersistenceType, aOriginMetadata.mOrigin));
+
+    QM_TRY_INSPECT(const bool& created, EnsureOriginDirectory(*directory));
+
+    if (created) {
+      const int64_t timestamp =
+          NoteOriginDirectoryCreated(aOriginMetadata, /* aPersisted */ false);
+
+      // Only creating .metadata-v2 to reduce IO.
+      QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(*directory, timestamp,
+                                                    /* aPersisted */ false,
+                                                    aOriginMetadata)));
+    }
+
+    // TODO: If the metadata file exists and we didn't call
+    //       LoadFullOriginMetadataWithRestore for it (because the quota info
+    //       was loaded from the cache), then the group in the metadata file
+    //       may be wrong, so it should be checked and eventually updated.
+    //       It's not a big deal that we are not doing it here, because the
+    //       origin will be marked as "accessed", so
+    //       LoadFullOriginMetadataWithRestore will be called for the metadata
+    //       file in next session in LoadQuotaFromCache.
+
+    return std::pair(std::move(directory), created);
+  };
+
+  return ExecuteOriginInitialization(
+      aOriginMetadata.mOrigin, OriginInitialization::TemporaryOrigin,
+      "dom::quota::FirstOriginInitializationAttempt::TemporaryOrigin"_ns,
+      innerFunc);
+}
+
+nsresult QuotaManager::EnsureTemporaryStorageIsInitialized() {
+  AssertIsOnIOThread();
+  MOZ_DIAGNOSTIC_ASSERT(mStorageConnection);
+
+  const auto innerFunc =
+      [&](const auto& firstInitializationAttempt) -> nsresult {
+    if (mTemporaryStorageInitialized) {
+      MOZ_ASSERT(firstInitializationAttempt.Recorded());
+      return NS_OK;
+    }
+
+    QM_TRY_INSPECT(
+        const auto& storageDir,
+        MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<nsIFile>,
+                                MOZ_SELECT_OVERLOAD(do_CreateInstance),
+                                NS_LOCAL_FILE_CONTRACTID));
+
+    QM_TRY(MOZ_TO_RESULT(storageDir->InitWithPath(GetStoragePath())));
+
+    // The storage directory must exist before calling GetTemporaryStorageLimit.
+    QM_TRY_INSPECT(const bool& created, EnsureDirectory(*storageDir));
+
+    Unused << created;
+
+    QM_TRY_UNWRAP(mTemporaryStorageLimit,
+                  GetTemporaryStorageLimit(*storageDir));
+
+    QM_TRY(MOZ_TO_RESULT(LoadQuota()));
+
+    mTemporaryStorageInitialized = true;
+
+    CleanupTemporaryStorage();
+
+    if (mCacheUsable) {
+      QM_TRY(InvalidateCache(*mStorageConnection));
+    }
+
+    return NS_OK;
+  };
+
+  return ExecuteInitialization(
+      Initialization::TemporaryStorage,
+      "dom::quota::FirstInitializationAttempt::TemporaryStorage"_ns, innerFunc);
+}
+
+RefPtr<BoolPromise> QuotaManager::ShutdownStorage() {
+  if (!mShuttingDownStorage) {
+    mShuttingDownStorage = true;
+
+    auto shutdownStorageOp = MakeRefPtr<ShutdownStorageOp>();
+
+    RegisterNormalOriginOp(*shutdownStorageOp);
+
+    shutdownStorageOp->RunImmediately();
+
+    shutdownStorageOp->OnResults()->Then(
+        GetCurrentSerialEventTarget(), __func__,
+        [self = RefPtr<QuotaManager>(this)](bool aResolveValue) {
+          self->mShuttingDownStorage = false;
+
+          self->mShutdownStoragePromiseHolder.ResolveIfExists(aResolveValue,
+                                                              __func__);
+        },
+        [self = RefPtr<QuotaManager>(this)](nsresult aRejectValue) {
+          self->mShuttingDownStorage = false;
+
+          self->mShutdownStoragePromiseHolder.RejectIfExists(aRejectValue,
+                                                             __func__);
+        });
+  }
+
+  return mShutdownStoragePromiseHolder.Ensure(__func__);
+}
+
+void QuotaManager::ShutdownStorageInternal() {
+  AssertIsOnIOThread();
+
+  if (mStorageConnection) {
+    mInitializationInfo.ResetOriginInitializationInfos();
+    mInitializedOrigins.Clear();
+
+    if (mTemporaryStorageInitialized) {
+      if (mCacheUsable) {
+        UnloadQuota();
+      } else {
+        RemoveQuota();
+      }
+
+      mTemporaryStorageInitialized = false;
+    }
+
+    ReleaseIOThreadObjects();
+
+    mStorageConnection = nullptr;
+    mCacheUsable = false;
+  }
+
+  mInitializationInfo.ResetFirstInitializationAttempts();
+}
+
+Result<bool, nsresult> QuotaManager::EnsureOriginDirectory(
+    nsIFile& aDirectory) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aDirectory, Exists));
+
+  if (!exists) {
+    QM_TRY_INSPECT(
+        const auto& leafName,
+        MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsString, aDirectory, GetLeafName)
+            .map([](const auto& leafName) {
+              return NS_ConvertUTF16toUTF8(leafName);
+            }));
+
+    QM_TRY(OkIf(IsSanitizedOriginValid(leafName)), Err(NS_ERROR_FAILURE),
+           [](const auto&) {
+             QM_WARNING(
+                 "Preventing creation of a new origin directory which is not "
+                 "supported by our origin parser or is obsolete!");
+           });
+  }
+
+  QM_TRY_RETURN(EnsureDirectory(aDirectory));
+}
+
+nsresult QuotaManager::AboutToClearOrigins(
+    const Nullable<PersistenceType>& aPersistenceType,
+    const OriginScope& aOriginScope,
+    const Nullable<Client::Type>& aClientType) {
+  AssertIsOnIOThread();
+
+  if (aClientType.IsNull()) {
+    for (Client::Type type : AllClientTypes()) {
+      QM_TRY(MOZ_TO_RESULT((*mClients)[type]->AboutToClearOrigins(
+          aPersistenceType, aOriginScope)));
+    }
+  } else {
+    QM_TRY(MOZ_TO_RESULT((*mClients)[aClientType.Value()]->AboutToClearOrigins(
+        aPersistenceType, aOriginScope)));
+  }
+
+  return NS_OK;
+}
+
+void QuotaManager::OriginClearCompleted(
+    PersistenceType aPersistenceType, const nsACString& aOrigin,
+    const Nullable<Client::Type>& aClientType) {
+  AssertIsOnIOThread();
+
+  if (aClientType.IsNull()) {
+    if (aPersistenceType == PERSISTENCE_TYPE_PERSISTENT) {
+      mInitializedOrigins.RemoveElement(aOrigin);
+    }
+
+    for (Client::Type type : AllClientTypes()) {
+      (*mClients)[type]->OnOriginClearCompleted(aPersistenceType, aOrigin);
+    }
+  } else {
+    (*mClients)[aClientType.Value()]->OnOriginClearCompleted(aPersistenceType,
+                                                             aOrigin);
+  }
+}
+
+Client* QuotaManager::GetClient(Client::Type aClientType) {
+  MOZ_ASSERT(aClientType >= Client::IDB);
+  MOZ_ASSERT(aClientType < Client::TypeMax());
+
+  return (*mClients)[aClientType];
+}
+
+const AutoTArray<Client::Type, Client::TYPE_MAX>&
+QuotaManager::AllClientTypes() {
+  if (CachedNextGenLocalStorageEnabled()) {
+    return *mAllClientTypes;
+  }
+  return *mAllClientTypesExceptLS;
+}
+
+uint64_t QuotaManager::GetGroupLimit() const {
+  // To avoid one group evicting all the rest, limit the amount any one group
+  // can use to 20% resp. a fifth. To prevent individual sites from using
+  // exorbitant amounts of storage where there is a lot of free space, cap the
+  // group limit to 10GB.
+  const auto x = std::min<uint64_t>(mTemporaryStorageLimit / 5, 10 GB);
+
+  // In low-storage situations, make an exception (while not exceeding the total
+  // storage limit).
+  return std::min<uint64_t>(mTemporaryStorageLimit,
+                            std::max<uint64_t>(x, 10 MB));
+}
+
+std::pair<uint64_t, uint64_t> QuotaManager::GetUsageAndLimitForEstimate(
+    const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  uint64_t totalGroupUsage = 0;
+
+  {
+    MutexAutoLock lock(mQuotaMutex);
+
+    GroupInfoPair* pair;
+    if (mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+      for (const PersistenceType type : kBestEffortPersistenceTypes) {
+        RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(type);
+        if (groupInfo) {
+          if (type == PERSISTENCE_TYPE_DEFAULT) {
+            RefPtr<OriginInfo> originInfo =
+                groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+
+            if (originInfo && originInfo->LockedPersisted()) {
+              return std::pair(mTemporaryStorageUsage, mTemporaryStorageLimit);
+            }
+          }
+
+          AssertNoOverflow(totalGroupUsage, groupInfo->mUsage);
+          totalGroupUsage += groupInfo->mUsage;
+        }
+      }
+    }
+  }
+
+  return std::pair(totalGroupUsage, GetGroupLimit());
+}
+
+uint64_t QuotaManager::GetOriginUsage(
+    const PrincipalMetadata& aPrincipalMetadata) {
+  AssertIsOnIOThread();
+
+  uint64_t usage = 0;
+
+  {
+    MutexAutoLock lock(mQuotaMutex);
+
+    GroupInfoPair* pair;
+    if (mGroupInfoPairs.Get(aPrincipalMetadata.mGroup, &pair)) {
+      for (const PersistenceType type : kBestEffortPersistenceTypes) {
+        RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(type);
+        if (groupInfo) {
+          RefPtr<OriginInfo> originInfo =
+              groupInfo->LockedGetOriginInfo(aPrincipalMetadata.mOrigin);
+          if (originInfo) {
+            AssertNoOverflow(usage, originInfo->LockedUsage());
+            usage += originInfo->LockedUsage();
+          }
+        }
+      }
+    }
+  }
+
+  return usage;
+}
+
+Maybe<FullOriginMetadata> QuotaManager::GetFullOriginMetadata(
+    const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+  MOZ_DIAGNOSTIC_ASSERT(mStorageConnection);
+  MOZ_DIAGNOSTIC_ASSERT(mTemporaryStorageInitialized);
+
+  MutexAutoLock lock(mQuotaMutex);
+
+  RefPtr<OriginInfo> originInfo =
+      LockedGetOriginInfo(aOriginMetadata.mPersistenceType, aOriginMetadata);
+  if (originInfo) {
+    return Some(originInfo->LockedFlattenToFullOriginMetadata());
+  }
+
+  return Nothing();
+}
+
+void QuotaManager::NotifyStoragePressure(uint64_t aUsage) {
+  mQuotaMutex.AssertNotCurrentThreadOwns();
+
+  RefPtr<StoragePressureRunnable> storagePressureRunnable =
+      new StoragePressureRunnable(aUsage);
+
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(storagePressureRunnable));
+}
+
+// static
+void QuotaManager::GetStorageId(PersistenceType aPersistenceType,
+                                const nsACString& aOrigin,
+                                Client::Type aClientType,
+                                nsACString& aDatabaseId) {
+  nsAutoCString str;
+  str.AppendInt(aPersistenceType);
+  str.Append('*');
+  str.Append(aOrigin);
+  str.Append('*');
+  str.AppendInt(aClientType);
+
+  aDatabaseId = str;
+}
+
+// static
+bool QuotaManager::IsPrincipalInfoValid(const PrincipalInfo& aPrincipalInfo) {
+  switch (aPrincipalInfo.type()) {
+    // A system principal is acceptable.
+    case PrincipalInfo::TSystemPrincipalInfo: {
+      return true;
+    }
+
+    // Validate content principals to ensure that the spec, originNoSuffix and
+    // baseDomain are sane.
+    case PrincipalInfo::TContentPrincipalInfo: {
+      const ContentPrincipalInfo& info =
+          aPrincipalInfo.get_ContentPrincipalInfo();
+
+      // Verify the principal spec parses.
+      RefPtr<MozURL> specURL;
+      nsresult rv = MozURL::Init(getter_AddRefs(specURL), info.spec());
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        QM_WARNING("A URL %s is not recognized by MozURL", info.spec().get());
+        return false;
+      }
+
+      // Verify the principal originNoSuffix matches spec.
+      nsCString originNoSuffix;
+      specURL->Origin(originNoSuffix);
+
+      if (NS_WARN_IF(originNoSuffix != info.originNoSuffix())) {
+        QM_WARNING("originNoSuffix (%s) doesn't match passed one (%s)!",
+                   originNoSuffix.get(), info.originNoSuffix().get());
+        return false;
+      }
+
+      if (NS_WARN_IF(info.originNoSuffix().EqualsLiteral(kChromeOrigin))) {
+        return false;
+      }
+
+      if (NS_WARN_IF(info.originNoSuffix().FindChar('^', 0) != -1)) {
+        QM_WARNING("originNoSuffix (%s) contains the '^' character!",
+                   info.originNoSuffix().get());
+        return false;
+      }
+
+      // Verify the principal baseDomain exists.
+      if (NS_WARN_IF(info.baseDomain().IsVoid())) {
+        return false;
+      }
+
+      // Verify the principal baseDomain matches spec.
+      nsCString baseDomain;
+      rv = specURL->BaseDomain(baseDomain);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return false;
+      }
+
+      if (NS_WARN_IF(baseDomain != info.baseDomain())) {
+        QM_WARNING("baseDomain (%s) doesn't match passed one (%s)!",
+                   baseDomain.get(), info.baseDomain().get());
+        return false;
+      }
+
+      return true;
+    }
+
+    default: {
+      break;
+    }
+  }
+
+  // Null and expanded principals are not acceptable.
+  return false;
+}
+
+// static
+PrincipalMetadata QuotaManager::GetInfoFromValidatedPrincipalInfo(
+    const PrincipalInfo& aPrincipalInfo) {
+  MOZ_ASSERT(IsPrincipalInfoValid(aPrincipalInfo));
+
+  switch (aPrincipalInfo.type()) {
+    case PrincipalInfo::TSystemPrincipalInfo: {
+      return GetInfoForChrome();
+    }
+
+    case PrincipalInfo::TContentPrincipalInfo: {
+      const ContentPrincipalInfo& info =
+          aPrincipalInfo.get_ContentPrincipalInfo();
+
+      PrincipalMetadata principalMetadata;
+
+      info.attrs().CreateSuffix(principalMetadata.mSuffix);
+
+      principalMetadata.mGroup = info.baseDomain() + principalMetadata.mSuffix;
+
+      principalMetadata.mOrigin =
+          info.originNoSuffix() + principalMetadata.mSuffix;
+
+      return principalMetadata;
+    }
+
+    default: {
+      MOZ_CRASH("Should never get here!");
+    }
+  }
+}
+
+// static
+nsAutoCString QuotaManager::GetOriginFromValidatedPrincipalInfo(
+    const PrincipalInfo& aPrincipalInfo) {
+  MOZ_ASSERT(IsPrincipalInfoValid(aPrincipalInfo));
+
+  switch (aPrincipalInfo.type()) {
+    case PrincipalInfo::TSystemPrincipalInfo: {
+      return nsAutoCString{GetOriginForChrome()};
+    }
+
+    case PrincipalInfo::TContentPrincipalInfo: {
+      const ContentPrincipalInfo& info =
+          aPrincipalInfo.get_ContentPrincipalInfo();
+
+      nsAutoCString suffix;
+
+      info.attrs().CreateSuffix(suffix);
+
+      return info.originNoSuffix() + suffix;
+    }
+
+    default: {
+      MOZ_CRASH("Should never get here!");
+    }
+  }
+}
+
+// static
+Result<PrincipalMetadata, nsresult> QuotaManager::GetInfoFromPrincipal(
+    nsIPrincipal* aPrincipal) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  if (aPrincipal->IsSystemPrincipal()) {
+    return GetInfoForChrome();
+  }
+
+  if (aPrincipal->GetIsNullPrincipal()) {
+    NS_WARNING("IndexedDB not supported from this principal!");
+    return Err(NS_ERROR_FAILURE);
+  }
+
+  PrincipalMetadata principalMetadata;
+
+  QM_TRY(MOZ_TO_RESULT(aPrincipal->GetOrigin(principalMetadata.mOrigin)));
+
+  if (principalMetadata.mOrigin.EqualsLiteral(kChromeOrigin)) {
+    NS_WARNING("Non-chrome principal can't use chrome origin!");
+    return Err(NS_ERROR_FAILURE);
+  }
+
+  aPrincipal->OriginAttributesRef().CreateSuffix(principalMetadata.mSuffix);
+
+  nsAutoCString baseDomain;
+  QM_TRY(MOZ_TO_RESULT(aPrincipal->GetBaseDomain(baseDomain)));
+
+  MOZ_ASSERT(!baseDomain.IsEmpty());
+
+  principalMetadata.mGroup = baseDomain + principalMetadata.mSuffix;
+
+  return principalMetadata;
+}
+
+// static
+Result<nsAutoCString, nsresult> QuotaManager::GetOriginFromPrincipal(
+    nsIPrincipal* aPrincipal) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  if (aPrincipal->IsSystemPrincipal()) {
+    return nsAutoCString{GetOriginForChrome()};
+  }
+
+  if (aPrincipal->GetIsNullPrincipal()) {
+    NS_WARNING("IndexedDB not supported from this principal!");
+    return Err(NS_ERROR_FAILURE);
+  }
+
+  QM_TRY_UNWRAP(const auto origin, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsAutoCString, aPrincipal, GetOrigin));
+
+  if (origin.EqualsLiteral(kChromeOrigin)) {
+    NS_WARNING("Non-chrome principal can't use chrome origin!");
+    return Err(NS_ERROR_FAILURE);
+  }
+
+  return origin;
+}
+
+// static
+Result<nsAutoCString, nsresult> QuotaManager::GetOriginFromWindow(
+    nsPIDOMWindowOuter* aWindow) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aWindow);
+
+  nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(aWindow);
+  QM_TRY(OkIf(sop), Err(NS_ERROR_FAILURE));
+
+  nsCOMPtr<nsIPrincipal> principal = sop->GetPrincipal();
+  QM_TRY(OkIf(principal), Err(NS_ERROR_FAILURE));
+
+  QM_TRY_RETURN(GetOriginFromPrincipal(principal));
+}
+
+// static
+PrincipalMetadata QuotaManager::GetInfoForChrome() {
+  return {{}, GetOriginForChrome(), GetOriginForChrome()};
+}
+
+// static
+nsLiteralCString QuotaManager::GetOriginForChrome() {
+  return nsLiteralCString{kChromeOrigin};
+}
+
+// static
+bool QuotaManager::IsOriginInternal(const nsACString& aOrigin) {
+  MOZ_ASSERT(!aOrigin.IsEmpty());
+
+  // The first prompt is not required for these origins.
+  if (aOrigin.EqualsLiteral(kChromeOrigin) ||
+      StringBeginsWith(aOrigin, nsDependentCString(kAboutHomeOriginPrefix)) ||
+      StringBeginsWith(aOrigin, nsDependentCString(kIndexedDBOriginPrefix)) ||
+      StringBeginsWith(aOrigin, nsDependentCString(kResourceOriginPrefix))) {
+    return true;
+  }
+
+  return false;
+}
+
+// static
+bool QuotaManager::AreOriginsEqualOnDisk(const nsACString& aOrigin1,
+                                         const nsACString& aOrigin2) {
+  return MakeSanitizedOriginCString(aOrigin1) ==
+         MakeSanitizedOriginCString(aOrigin2);
+}
+
+// static
+Result<PrincipalInfo, nsresult> QuotaManager::ParseOrigin(
+    const nsACString& aOrigin) {
+  // An origin string either corresponds to a SystemPrincipalInfo or a
+  // ContentPrincipalInfo, see
+  // QuotaManager::GetOriginFromValidatedPrincipalInfo.
+
+  if (aOrigin.Equals(kChromeOrigin)) {
+    return PrincipalInfo{SystemPrincipalInfo{}};
+  }
+
+  ContentPrincipalInfo contentPrincipalInfo;
+
+  nsCString originalSuffix;
+  const OriginParser::ResultType result = OriginParser::ParseOrigin(
+      MakeSanitizedOriginCString(aOrigin), contentPrincipalInfo.spec(),
+      &contentPrincipalInfo.attrs(), originalSuffix);
+  QM_TRY(OkIf(result == OriginParser::ValidOrigin), Err(NS_ERROR_FAILURE));
+
+  return PrincipalInfo{std::move(contentPrincipalInfo)};
+}
+
+// static
+void QuotaManager::InvalidateQuotaCache() { gInvalidateQuotaCache = true; }
+
+uint64_t QuotaManager::LockedCollectOriginsForEviction(
+    uint64_t aMinSizeToBeFreed, nsTArray<RefPtr<OriginDirectoryLock>>& aLocks) {
+  mQuotaMutex.AssertCurrentThreadOwns();
+
+  RefPtr<CollectOriginsHelper> helper =
+      new CollectOriginsHelper(mQuotaMutex, aMinSizeToBeFreed);
+
+  // Unlock while calling out to XPCOM (code behind the dispatch method needs
+  // to acquire its own lock which can potentially lead to a deadlock and it
+  // also calls an observer that can do various stuff like IO, so it's better
+  // to not hold our mutex while that happens).
+  {
+    MutexAutoUnlock autoUnlock(mQuotaMutex);
+
+    MOZ_ALWAYS_SUCCEEDS(mOwningThread->Dispatch(helper, NS_DISPATCH_NORMAL));
+  }
+
+  return helper->BlockAndReturnOriginsForEviction(aLocks);
+}
+
+void QuotaManager::LockedRemoveQuotaForOrigin(
+    const OriginMetadata& aOriginMetadata) {
+  mQuotaMutex.AssertCurrentThreadOwns();
+  MOZ_ASSERT(aOriginMetadata.mPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+  GroupInfoPair* pair;
+  if (!mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+    return;
+  }
+
+  MOZ_ASSERT(pair);
+
+  if (RefPtr<GroupInfo> groupInfo =
+          pair->LockedGetGroupInfo(aOriginMetadata.mPersistenceType)) {
+    groupInfo->LockedRemoveOriginInfo(aOriginMetadata.mOrigin);
+
+    if (!groupInfo->LockedHasOriginInfos()) {
+      pair->LockedClearGroupInfo(aOriginMetadata.mPersistenceType);
+
+      if (!pair->LockedHasGroupInfos()) {
+        mGroupInfoPairs.Remove(aOriginMetadata.mGroup);
+      }
+    }
+  }
+}
+
+already_AddRefed<GroupInfo> QuotaManager::LockedGetOrCreateGroupInfo(
+    PersistenceType aPersistenceType, const nsACString& aSuffix,
+    const nsACString& aGroup) {
+  mQuotaMutex.AssertCurrentThreadOwns();
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+  GroupInfoPair* const pair =
+      mGroupInfoPairs.GetOrInsertNew(aGroup, aSuffix, aGroup);
+
+  RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(aPersistenceType);
+  if (!groupInfo) {
+    groupInfo = new GroupInfo(pair, aPersistenceType);
+    pair->LockedSetGroupInfo(aPersistenceType, groupInfo);
+  }
+
+  return groupInfo.forget();
+}
+
+already_AddRefed<OriginInfo> QuotaManager::LockedGetOriginInfo(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata) {
+  mQuotaMutex.AssertCurrentThreadOwns();
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+  GroupInfoPair* pair;
+  if (mGroupInfoPairs.Get(aOriginMetadata.mGroup, &pair)) {
+    RefPtr<GroupInfo> groupInfo = pair->LockedGetGroupInfo(aPersistenceType);
+    if (groupInfo) {
+      return groupInfo->LockedGetOriginInfo(aOriginMetadata.mOrigin);
+    }
+  }
+
+  return nullptr;
+}
+
+template <typename Iterator>
+void QuotaManager::MaybeInsertNonPersistedOriginInfos(
+    Iterator aDest, const RefPtr<GroupInfo>& aTemporaryGroupInfo,
+    const RefPtr<GroupInfo>& aDefaultGroupInfo) {
+  const auto copy = [&aDest](const GroupInfo& groupInfo) {
+    std::copy_if(
+        groupInfo.mOriginInfos.cbegin(), groupInfo.mOriginInfos.cend(), aDest,
+        [](const auto& originInfo) { return !originInfo->LockedPersisted(); });
+  };
+
+  if (aTemporaryGroupInfo) {
+    MOZ_ASSERT(PERSISTENCE_TYPE_TEMPORARY ==
+               aTemporaryGroupInfo->GetPersistenceType());
+
+    copy(*aTemporaryGroupInfo);
+  }
+  if (aDefaultGroupInfo) {
+    MOZ_ASSERT(PERSISTENCE_TYPE_DEFAULT ==
+               aDefaultGroupInfo->GetPersistenceType());
+
+    copy(*aDefaultGroupInfo);
+  }
+}
+
+template <typename Collect, typename Pred>
+QuotaManager::OriginInfosFlatTraversable
+QuotaManager::CollectLRUOriginInfosUntil(Collect&& aCollect, Pred&& aPred) {
+  OriginInfosFlatTraversable originInfos;
+
+  std::forward<Collect>(aCollect)(MakeBackInserter(originInfos));
+
+  originInfos.Sort(OriginInfoAccessTimeComparator());
+
+  const auto foundIt = std::find_if(originInfos.cbegin(), originInfos.cend(),
+                                    std::forward<Pred>(aPred));
+
+  originInfos.TruncateLength(foundIt - originInfos.cbegin());
+
+  return originInfos;
+}
+
+QuotaManager::OriginInfosNestedTraversable
+QuotaManager::GetOriginInfosExceedingGroupLimit() const {
+  MutexAutoLock lock(mQuotaMutex);
+
+  OriginInfosNestedTraversable originInfos;
+
+  for (const auto& entry : mGroupInfoPairs) {
+    const auto& pair = entry.GetData();
+
+    MOZ_ASSERT(!entry.GetKey().IsEmpty());
+    MOZ_ASSERT(pair);
+
+    uint64_t groupUsage = 0;
+
+    const RefPtr<GroupInfo> temporaryGroupInfo =
+        pair->LockedGetGroupInfo(PERSISTENCE_TYPE_TEMPORARY);
+    if (temporaryGroupInfo) {
+      groupUsage += temporaryGroupInfo->mUsage;
+    }
+
+    const RefPtr<GroupInfo> defaultGroupInfo =
+        pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT);
+    if (defaultGroupInfo) {
+      groupUsage += defaultGroupInfo->mUsage;
+    }
+
+    if (groupUsage > 0) {
+      QuotaManager* quotaManager = QuotaManager::Get();
+      MOZ_ASSERT(quotaManager, "Shouldn't be null!");
+
+      if (groupUsage > quotaManager->GetGroupLimit()) {
+        originInfos.AppendElement(CollectLRUOriginInfosUntil(
+            [&temporaryGroupInfo, &defaultGroupInfo](auto inserter) {
+              MaybeInsertNonPersistedOriginInfos(
+                  std::move(inserter), temporaryGroupInfo, defaultGroupInfo);
+            },
+            [&groupUsage, quotaManager](const auto& originInfo) {
+              groupUsage -= originInfo->LockedUsage();
+
+              return groupUsage <= quotaManager->GetGroupLimit();
+            }));
+      }
+    }
+  }
+
+  return originInfos;
+}
+
+QuotaManager::OriginInfosNestedTraversable
+QuotaManager::GetOriginInfosExceedingGlobalLimit() const {
+  MutexAutoLock lock(mQuotaMutex);
+
+  QuotaManager::OriginInfosNestedTraversable res;
+  res.AppendElement(CollectLRUOriginInfosUntil(
+      // XXX The lambda only needs to capture this, but due to Bug 1421435 it
+      // can't.
+      [&](auto inserter) {
+        for (const auto& entry : mGroupInfoPairs) {
+          const auto& pair = entry.GetData();
+
+          MOZ_ASSERT(!entry.GetKey().IsEmpty());
+          MOZ_ASSERT(pair);
+
+          MaybeInsertNonPersistedOriginInfos(
+              inserter, pair->LockedGetGroupInfo(PERSISTENCE_TYPE_TEMPORARY),
+              pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT));
+        }
+      },
+      [temporaryStorageUsage = mTemporaryStorageUsage,
+       temporaryStorageLimit = mTemporaryStorageLimit,
+       doomedUsage = uint64_t{0}](const auto& originInfo) mutable {
+        if (temporaryStorageUsage - doomedUsage <= temporaryStorageLimit) {
+          return true;
+        }
+
+        doomedUsage += originInfo->LockedUsage();
+        return false;
+      }));
+
+  return res;
+}
+
+void QuotaManager::ClearOrigins(
+    const OriginInfosNestedTraversable& aDoomedOriginInfos) {
+  AssertIsOnIOThread();
+
+  // If we are in shutdown, we could break off early from clearing origins.
+  // In such cases, we would like to track the ones that were already cleared
+  // up, such that other essential cleanup could be performed on clearedOrigins.
+  // clearedOrigins is used in calls to LockedRemoveQuotaForOrigin and
+  // OriginClearCompleted below. We could have used a collection of OriginInfos
+  // rather than flattening them to OriginMetadata but groupInfo in OriginInfo
+  // is just a raw ptr and LockedRemoveQuotaForOrigin might delete groupInfo and
+  // as a result, we would not be able to get origin persistence type required
+  // in OriginClearCompleted call after lockedRemoveQuotaForOrigin call.
+  nsTArray<OriginMetadata> clearedOrigins;
+
+  // XXX Does this need to be done a) in order and/or b) sequentially?
+  for (const auto& doomedOriginInfo :
+       Flatten<OriginInfosFlatTraversable::value_type>(aDoomedOriginInfos)) {
+#ifdef DEBUG
+    {
+      MutexAutoLock lock(mQuotaMutex);
+      MOZ_ASSERT(!doomedOriginInfo->LockedPersisted());
+    }
+#endif
+
+    //  TODO: We are currently only checking for this flag here which
+    //  means that we cannot break off once we start cleaning an origin. It
+    //  could be better if we could check for shutdown flag while cleaning an
+    //  origin such that we could break off early from the cleaning process if
+    //  we are stuck cleaning on one huge origin. Bug1797098 has been filed to
+    //  track this.
+    if (QuotaManager::IsShuttingDown()) {
+      break;
+    }
+
+    DeleteFilesForOrigin(doomedOriginInfo->mGroupInfo->mPersistenceType,
+                         doomedOriginInfo->mOrigin);
+
+    clearedOrigins.AppendElement(doomedOriginInfo->FlattenToOriginMetadata());
+  }
+
+  {
+    MutexAutoLock lock(mQuotaMutex);
+
+    for (const auto& clearedOrigin : clearedOrigins) {
+      LockedRemoveQuotaForOrigin(clearedOrigin);
+    }
+  }
+
+  for (const auto& clearedOrigin : clearedOrigins) {
+    OriginClearCompleted(clearedOrigin.mPersistenceType, clearedOrigin.mOrigin,
+                         Nullable<Client::Type>());
+  }
+}
+
+void QuotaManager::CleanupTemporaryStorage() {
+  AssertIsOnIOThread();
+
+  // Evicting origins that exceed their group limit also affects the global
+  // temporary storage usage, so these steps have to be taken sequentially.
+  // Combining them doesn't seem worth the added complexity.
+  ClearOrigins(GetOriginInfosExceedingGroupLimit());
+  ClearOrigins(GetOriginInfosExceedingGlobalLimit());
+
+  if (mTemporaryStorageUsage > mTemporaryStorageLimit) {
+    // If disk space is still low after origin clear, notify storage pressure.
+    NotifyStoragePressure(mTemporaryStorageUsage);
+  }
+}
+
+void QuotaManager::DeleteFilesForOrigin(PersistenceType aPersistenceType,
+                                        const nsACString& aOrigin) {
+  QM_TRY_INSPECT(const auto& directory,
+                 GetDirectoryForOrigin(aPersistenceType, aOrigin), QM_VOID);
+
+  nsresult rv = directory->Remove(true);
+  if (rv != NS_ERROR_FILE_NOT_FOUND && NS_FAILED(rv)) {
+    // This should never fail if we've closed all storage connections
+    // correctly...
+    NS_ERROR("Failed to remove directory!");
+  }
+}
+
+void QuotaManager::FinalizeOriginEviction(
+    nsTArray<RefPtr<OriginDirectoryLock>>&& aLocks) {
+  NS_ASSERTION(!NS_IsMainThread(), "Wrong thread!");
+
+  RefPtr<FinalizeOriginEvictionOp> op =
+      new FinalizeOriginEvictionOp(mOwningThread, std::move(aLocks));
+
+  if (IsOnIOThread()) {
+    op->RunOnIOThreadImmediately();
+  } else {
+    op->Dispatch();
+  }
+}
+
+Result<Ok, nsresult> QuotaManager::ArchiveOrigins(
+    const nsTArray<FullOriginMetadata>& aFullOriginMetadatas) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!aFullOriginMetadatas.IsEmpty());
+
+  QM_TRY_INSPECT(const auto& storageArchivesDir,
+                 QM_NewLocalFile(*mStorageArchivesPath));
+
+  // Create another subdir, so once we decide to remove all temporary archives,
+  // we can remove only the subdir and the parent directory can still be used
+  // for something else or similar in future. Otherwise, we would have to
+  // figure out a new name for it.
+  QM_TRY(MOZ_TO_RESULT(storageArchivesDir->Append(u"0"_ns)));
+
+  PRExplodedTime now;
+  PR_ExplodeTime(PR_Now(), PR_LocalTimeParameters, &now);
+
+  const auto dateStr =
+      nsPrintfCString("%04hd-%02" PRId32 "-%02" PRId32, now.tm_year,
+                      now.tm_month + 1, now.tm_mday);
+
+  QM_TRY_INSPECT(
+      const auto& storageArchiveDir,
+      CloneFileAndAppend(*storageArchivesDir, NS_ConvertASCIItoUTF16(dateStr)));
+
+  QM_TRY(MOZ_TO_RESULT(
+      storageArchiveDir->CreateUnique(nsIFile::DIRECTORY_TYPE, 0700)));
+
+  QM_TRY_INSPECT(const auto& defaultStorageArchiveDir,
+                 CloneFileAndAppend(*storageArchiveDir,
+                                    nsLiteralString(DEFAULT_DIRECTORY_NAME)));
+
+  QM_TRY_INSPECT(const auto& temporaryStorageArchiveDir,
+                 CloneFileAndAppend(*storageArchiveDir,
+                                    nsLiteralString(TEMPORARY_DIRECTORY_NAME)));
+
+  for (const auto& fullOriginMetadata : aFullOriginMetadatas) {
+    MOZ_ASSERT(
+        IsBestEffortPersistenceType(fullOriginMetadata.mPersistenceType));
+
+    QM_TRY_INSPECT(const auto& directory,
+                   GetDirectoryForOrigin(fullOriginMetadata.mPersistenceType,
+                                         fullOriginMetadata.mOrigin));
+
+    // The origin could have been removed, for example due to corruption.
+    QM_TRY_INSPECT(
+        const auto& moved,
+        QM_OR_ELSE_WARN_IF(
+            // Expression.
+            MOZ_TO_RESULT(
+                directory->MoveTo(fullOriginMetadata.mPersistenceType ==
+                                          PERSISTENCE_TYPE_DEFAULT
+                                      ? defaultStorageArchiveDir
+                                      : temporaryStorageArchiveDir,
+                                  u""_ns))
+                .map([](Ok) { return true; }),
+            // Predicate.
+            ([](const nsresult rv) { return rv == NS_ERROR_FILE_NOT_FOUND; }),
+            // Fallback.
+            ErrToOk<false>));
+
+    if (moved) {
+      RemoveQuotaForOrigin(fullOriginMetadata.mPersistenceType,
+                           fullOriginMetadata);
+    }
+  }
+
+  return Ok{};
+}
+
+auto QuotaManager::GetDirectoryLockTable(PersistenceType aPersistenceType)
+    -> DirectoryLockTable& {
+  switch (aPersistenceType) {
+    case PERSISTENCE_TYPE_TEMPORARY:
+      return mTemporaryDirectoryLockTable;
+    case PERSISTENCE_TYPE_DEFAULT:
+      return mDefaultDirectoryLockTable;
+
+    case PERSISTENCE_TYPE_PERSISTENT:
+    case PERSISTENCE_TYPE_INVALID:
+    default:
+      MOZ_CRASH("Bad persistence type value!");
+  }
+}
+
+bool QuotaManager::IsSanitizedOriginValid(const nsACString& aSanitizedOrigin) {
+  AssertIsOnIOThread();
+
+  // Do not parse this sanitized origin string, if we already parsed it.
+  return mValidOrigins.LookupOrInsertWith(
+      aSanitizedOrigin, [&aSanitizedOrigin] {
+        nsCString spec;
+        OriginAttributes attrs;
+        nsCString originalSuffix;
+        const auto result = OriginParser::ParseOrigin(aSanitizedOrigin, spec,
+                                                      &attrs, originalSuffix);
+
+        return result == OriginParser::ValidOrigin;
+      });
+}
+
+int64_t QuotaManager::GenerateDirectoryLockId() {
+  const int64_t directorylockId = mNextDirectoryLockId;
+
+  if (CheckedInt64 result = CheckedInt64(mNextDirectoryLockId) + 1;
+      result.isValid()) {
+    mNextDirectoryLockId = result.value();
+  } else {
+    NS_WARNING("Quota manager has run out of ids for directory locks!");
+
+    // There's very little chance for this to happen given the max size of
+    // 64 bit integer but if it happens we can just reset mNextDirectoryLockId
+    // to zero since such old directory locks shouldn't exist anymore.
+    mNextDirectoryLockId = 0;
+  }
+
+  // TODO: Maybe add an assertion here to check that there is no existing
+  //       directory lock with given id.
+
+  return directorylockId;
+}
+
+template <typename Func>
+auto QuotaManager::ExecuteInitialization(const Initialization aInitialization,
+                                         Func&& aFunc)
+    -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                      Initialization, StringGenerator>&> {
+  return quota::ExecuteInitialization(mInitializationInfo, aInitialization,
+                                      std::forward<Func>(aFunc));
+}
+
+template <typename Func>
+auto QuotaManager::ExecuteInitialization(const Initialization aInitialization,
+                                         const nsACString& aContext,
+                                         Func&& aFunc)
+    -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                      Initialization, StringGenerator>&> {
+  return quota::ExecuteInitialization(mInitializationInfo, aInitialization,
+                                      aContext, std::forward<Func>(aFunc));
+}
+
+template <typename Func>
+auto QuotaManager::ExecuteOriginInitialization(
+    const nsACString& aOrigin, const OriginInitialization aInitialization,
+    const nsACString& aContext, Func&& aFunc)
+    -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                      Initialization, StringGenerator>&> {
+  return quota::ExecuteInitialization(
+      mInitializationInfo.MutableOriginInitializationInfoRef(
+          aOrigin, CreateIfNonExistent{}),
+      aInitialization, aContext, std::forward<Func>(aFunc));
+}
+
+/*******************************************************************************
+ * Local class implementations
+ ******************************************************************************/
+
+CollectOriginsHelper::CollectOriginsHelper(mozilla::Mutex& aMutex,
+                                           uint64_t aMinSizeToBeFreed)
+    : Runnable("dom::quota::CollectOriginsHelper"),
+      mMinSizeToBeFreed(aMinSizeToBeFreed),
+      mMutex(aMutex),
+      mCondVar(aMutex, "CollectOriginsHelper::mCondVar"),
+      mSizeToBeFreed(0),
+      mWaiting(true) {
+  MOZ_ASSERT(!NS_IsMainThread(), "Wrong thread!");
+  mMutex.AssertCurrentThreadOwns();
+}
+
+int64_t CollectOriginsHelper::BlockAndReturnOriginsForEviction(
+    nsTArray<RefPtr<OriginDirectoryLock>>& aLocks) {
+  MOZ_ASSERT(!NS_IsMainThread(), "Wrong thread!");
+  mMutex.AssertCurrentThreadOwns();
+
+  while (mWaiting) {
+    mCondVar.Wait();
+  }
+
+  mLocks.SwapElements(aLocks);
+  return mSizeToBeFreed;
+}
+
+NS_IMETHODIMP
+CollectOriginsHelper::Run() {
+  AssertIsOnBackgroundThread();
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  NS_ASSERTION(quotaManager, "Shouldn't be null!");
+
+  // We use extra stack vars here to avoid race detector warnings (the same
+  // memory accessed with and without the lock held).
+  nsTArray<RefPtr<OriginDirectoryLock>> locks;
+  uint64_t sizeToBeFreed =
+      quotaManager->CollectOriginsForEviction(mMinSizeToBeFreed, locks);
+
+  MutexAutoLock lock(mMutex);
+
+  NS_ASSERTION(mWaiting, "Huh?!");
+
+  mLocks.SwapElements(locks);
+  mSizeToBeFreed = sizeToBeFreed;
+  mWaiting = false;
+  mCondVar.Notify();
+
+  return NS_OK;
+}
+
+/*******************************************************************************
+ * OriginOperationBase
+ ******************************************************************************/
+
+NS_IMETHODIMP
+OriginOperationBase::Run() {
+  nsresult rv;
+
+  switch (mState) {
+    case State_Initial: {
+      rv = Init();
+      break;
+    }
+
+    case State_DirectoryOpenPending: {
+      rv = DirectoryOpen();
+      break;
+    }
+
+    case State_DirectoryWorkOpen: {
+      rv = DirectoryWork();
+      break;
+    }
+
+    case State_UnblockingOpen: {
+      UnblockOpen();
+      return NS_OK;
+    }
+
+    default:
+      MOZ_CRASH("Bad state!");
+  }
+
+  if (NS_WARN_IF(NS_FAILED(rv)) && mState != State_UnblockingOpen) {
+    Finish(rv);
+  }
+
+  return NS_OK;
+}
+
+nsresult OriginOperationBase::DirectoryOpen() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mState == State_DirectoryOpenPending);
+
+  QuotaManager* const quotaManager = QuotaManager::Get();
+  QM_TRY(OkIf(quotaManager), NS_ERROR_FAILURE);
+
+  // Must set this before dispatching otherwise we will race with the IO thread.
+  AdvanceState();
+
+  QM_TRY(MOZ_TO_RESULT(
+             quotaManager->IOThread()->Dispatch(this, NS_DISPATCH_NORMAL)),
+         NS_ERROR_FAILURE);
+
+  return NS_OK;
+}
+
+void OriginOperationBase::Finish(nsresult aResult) {
+  if (NS_SUCCEEDED(mResultCode)) {
+    mResultCode = aResult;
+  }
+
+  // Must set mState before dispatching otherwise we will race with the main
+  // thread.
+  mState = State_UnblockingOpen;
+
+  MOZ_ALWAYS_SUCCEEDS(mOwningThread->Dispatch(this, NS_DISPATCH_NORMAL));
+}
+
+nsresult OriginOperationBase::Init() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mState == State_Initial);
+
+  if (QuotaManager::IsShuttingDown()) {
+    return NS_ERROR_ABORT;
+  }
+
+  if (mNeedsQuotaManagerInit) {
+    QM_TRY(QuotaManager::EnsureCreated());
+  }
+
+  Open();
+
+  return NS_OK;
+}
+
+nsresult OriginOperationBase::DirectoryWork() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mState == State_DirectoryWorkOpen);
+
+  QuotaManager* const quotaManager = QuotaManager::Get();
+  QM_TRY(OkIf(quotaManager), NS_ERROR_FAILURE);
+
+  if (mNeedsStorageInit) {
+    QM_TRY(MOZ_TO_RESULT(quotaManager->EnsureStorageIsInitialized()));
+  }
+
+  QM_TRY(MOZ_TO_RESULT(DoDirectoryWork(*quotaManager)));
+
+  // Must set mState before dispatching otherwise we will race with the owning
+  // thread.
+  AdvanceState();
+
+  MOZ_ALWAYS_SUCCEEDS(mOwningThread->Dispatch(this, NS_DISPATCH_NORMAL));
+
+  return NS_OK;
+}
+
+void FinalizeOriginEvictionOp::Dispatch() {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(GetState() == State_Initial);
+
+  SetState(State_DirectoryOpenPending);
+
+  MOZ_ALWAYS_SUCCEEDS(mOwningThread->Dispatch(this, NS_DISPATCH_NORMAL));
+}
+
+void FinalizeOriginEvictionOp::RunOnIOThreadImmediately() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(GetState() == State_Initial);
+
+  SetState(State_DirectoryWorkOpen);
+
+  MOZ_ALWAYS_SUCCEEDS(this->Run());
+}
+
+void FinalizeOriginEvictionOp::Open() { MOZ_CRASH("Shouldn't get here!"); }
+
+nsresult FinalizeOriginEvictionOp::DoDirectoryWork(
+    QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("FinalizeOriginEvictionOp::DoDirectoryWork", OTHER);
+
+  for (const auto& lock : mLocks) {
+    aQuotaManager.OriginClearCompleted(
+        lock->GetPersistenceType(), lock->Origin(), Nullable<Client::Type>());
+  }
+
+  return NS_OK;
+}
+
+void FinalizeOriginEvictionOp::UnblockOpen() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(GetState() == State_UnblockingOpen);
+
+#ifdef DEBUG
+  NoteActorDestroyed();
+#endif
+
+  mLocks.Clear();
+
+  AdvanceState();
+}
+
+NS_IMPL_ISUPPORTS_INHERITED0(NormalOriginOperationBase, Runnable)
+
+RefPtr<DirectoryLock> NormalOriginOperationBase::CreateDirectoryLock() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(GetState() == State_DirectoryOpenPending);
+  MOZ_ASSERT(QuotaManager::Get());
+
+  return QuotaManager::Get()->CreateDirectoryLockInternal(
+      mPersistenceType, mOriginScope, mClientType, mExclusive);
+}
+
+void NormalOriginOperationBase::Open() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(GetState() == State_Initial);
+  MOZ_ASSERT(QuotaManager::Get());
+
+  AdvanceState();
+
+  RefPtr<DirectoryLock> directoryLock = CreateDirectoryLock();
+  if (directoryLock) {
+    directoryLock->Acquire(this);
+  } else {
+    QM_TRY(MOZ_TO_RESULT(DirectoryOpen()), QM_VOID,
+           [this](const nsresult rv) { Finish(rv); });
+  }
+}
+
+void NormalOriginOperationBase::UnblockOpen() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(GetState() == State_UnblockingOpen);
+
+  SendResults();
+
+  if (mDirectoryLock) {
+    mDirectoryLock = nullptr;
+  }
+
+  UnregisterNormalOriginOp(*this);
+
+  AdvanceState();
+}
+
+void NormalOriginOperationBase::DirectoryLockAcquired(DirectoryLock* aLock) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aLock);
+  MOZ_ASSERT(GetState() == State_DirectoryOpenPending);
+  MOZ_ASSERT(!mDirectoryLock);
+
+  mDirectoryLock = aLock;
+
+  QM_TRY(MOZ_TO_RESULT(DirectoryOpen()), QM_VOID,
+         [this](const nsresult rv) { Finish(rv); });
+}
+
+void NormalOriginOperationBase::DirectoryLockFailed() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(GetState() == State_DirectoryOpenPending);
+  MOZ_ASSERT(!mDirectoryLock);
+
+  Finish(NS_ERROR_FAILURE);
+}
+
+nsresult SaveOriginAccessTimeOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!mPersistenceType.IsNull());
+  MOZ_ASSERT(mOriginScope.IsOrigin());
+
+  AUTO_PROFILER_LABEL("SaveOriginAccessTimeOp::DoDirectoryWork", OTHER);
+
+  QM_TRY_INSPECT(const auto& file,
+                 aQuotaManager.GetDirectoryForOrigin(mPersistenceType.Value(),
+                                                     mOriginScope.GetOrigin()));
+
+  // The origin directory might not exist
+  // anymore, because it was deleted by a clear operation.
+  QM_TRY_INSPECT(const bool& exists, MOZ_TO_RESULT_INVOKE_MEMBER(file, Exists));
+
+  if (exists) {
+    QM_TRY(MOZ_TO_RESULT(file->Append(nsLiteralString(METADATA_V2_FILE_NAME))));
+
+    QM_TRY_INSPECT(const auto& stream,
+                   GetBinaryOutputStream(*file, FileFlag::Update));
+    MOZ_ASSERT(stream);
+
+    QM_TRY(MOZ_TO_RESULT(stream->Write64(mTimestamp)));
+  }
+
+  return NS_OK;
+}
+
+void SaveOriginAccessTimeOp::SendResults() {
+#ifdef DEBUG
+  NoteActorDestroyed();
+#endif
+}
+
+#ifdef DEBUG
+nsresult ShutdownStorageOp::DirectoryOpen() {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(mDirectoryLock);
+  mDirectoryLock->AssertIsAcquiredExclusively();
+
+  return NormalOriginOperationBase::DirectoryOpen();
+}
+#endif
+
+nsresult ShutdownStorageOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("ShutdownStorageOp::DoDirectoryWork", OTHER);
+
+  aQuotaManager.ShutdownStorageInternal();
+
+  return NS_OK;
+}
+
+void ShutdownStorageOp::SendResults() {
+#ifdef DEBUG
+  NoteActorDestroyed();
+#endif
+
+  if (NS_SUCCEEDED(mResultCode)) {
+    mPromiseHolder.ResolveIfExists(true, __func__);
+  } else {
+    mPromiseHolder.RejectIfExists(mResultCode, __func__);
+  }
+}
+
+NS_IMETHODIMP
+StoragePressureRunnable::Run() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIObserverService> obsSvc = mozilla::services::GetObserverService();
+  if (NS_WARN_IF(!obsSvc)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsISupportsPRUint64> wrapper =
+      do_CreateInstance(NS_SUPPORTS_PRUINT64_CONTRACTID);
+  if (NS_WARN_IF(!wrapper)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  wrapper->SetData(mUsage);
+
+  obsSvc->NotifyObservers(wrapper, "QuotaManager::StoragePressure", u"");
+
+  return NS_OK;
+}
+
+TimeStamp RecordQuotaInfoLoadTimeHelper::Start() {
+  AssertIsOnIOThread();
+
+  // XXX: If a OS sleep/wake occur after mStartTime is initialized but before
+  // gLastOSWake is set, then this time duration would still be recorded with
+  // key "Normal". We are assumming this is rather rare to happen.
+  mStartTime.init(TimeStamp::Now());
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(this));
+
+  return *mStartTime;
+}
+
+TimeStamp RecordQuotaInfoLoadTimeHelper::End() {
+  AssertIsOnIOThread();
+
+  mEndTime.init(TimeStamp::Now());
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(this));
+
+  return *mEndTime;
+}
+
+NS_IMETHODIMP
+RecordQuotaInfoLoadTimeHelper::Run() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (mInitializedTime.isSome()) {
+    // Keys for QM_QUOTA_INFO_LOAD_TIME_V0:
+    // Normal: Normal conditions.
+    // WasSuspended: There was a OS sleep so that it was suspended.
+    // TimeStampErr1: The recorded start time is unexpectedly greater than the
+    //                end time.
+    // TimeStampErr2: The initialized time for the recording class is unexpectly
+    //                greater than the last OS wake time.
+    const auto key = [this, wasSuspended = gLastOSWake > *mInitializedTime]() {
+      if (wasSuspended) {
+        return "WasSuspended"_ns;
+      }
+
+      // XXX File a bug if we have data for this key.
+      // We found negative values in our query in STMO for
+      // ScalarID::QM_REPOSITORIES_INITIALIZATION_TIME. This shouldn't happen
+      // because the documentation for TimeStamp::Now() says it returns a
+      // monotonically increasing number.
+      if (*mStartTime > *mEndTime) {
+        return "TimeStampErr1"_ns;
+      }
+
+      if (*mInitializedTime > gLastOSWake) {
+        return "TimeStampErr2"_ns;
+      }
+
+      return "Normal"_ns;
+    }();
+
+    Telemetry::AccumulateTimeDelta(Telemetry::QM_QUOTA_INFO_LOAD_TIME_V0, key,
+                                   *mStartTime, *mEndTime);
+
+    return NS_OK;
+  }
+
+  gLastOSWake = TimeStamp::Now();
+  mInitializedTime.init(gLastOSWake);
+
+  return NS_OK;
+}
+
+/*******************************************************************************
+ * Quota
+ ******************************************************************************/
+
+Quota::Quota()
+#ifdef DEBUG
+    : mActorDestroyed(false)
+#endif
+{
+}
+
+Quota::~Quota() { MOZ_ASSERT(mActorDestroyed); }
+
+bool Quota::VerifyRequestParams(const UsageRequestParams& aParams) const {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aParams.type() != UsageRequestParams::T__None);
+
+  switch (aParams.type()) {
+    case UsageRequestParams::TAllUsageParams:
+      break;
+
+    case UsageRequestParams::TOriginUsageParams: {
+      const OriginUsageParams& params = aParams.get_OriginUsageParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    default:
+      MOZ_CRASH("Should never get here!");
+  }
+
+  return true;
+}
+
+bool Quota::VerifyRequestParams(const RequestParams& aParams) const {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aParams.type() != RequestParams::T__None);
+
+  switch (aParams.type()) {
+    case RequestParams::TStorageNameParams:
+    case RequestParams::TStorageInitializedParams:
+    case RequestParams::TTemporaryStorageInitializedParams:
+    case RequestParams::TInitParams:
+    case RequestParams::TInitTemporaryStorageParams:
+      break;
+
+    case RequestParams::TInitializePersistentOriginParams: {
+      const InitializePersistentOriginParams& params =
+          aParams.get_InitializePersistentOriginParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TInitializeTemporaryOriginParams: {
+      const InitializeTemporaryOriginParams& params =
+          aParams.get_InitializeTemporaryOriginParams();
+
+      if (NS_WARN_IF(!IsBestEffortPersistenceType(params.persistenceType()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TGetFullOriginMetadataParams: {
+      const GetFullOriginMetadataParams& params =
+          aParams.get_GetFullOriginMetadataParams();
+      if (NS_WARN_IF(!IsBestEffortPersistenceType(params.persistenceType()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TClearOriginParams: {
+      const ClearResetOriginParams& params =
+          aParams.get_ClearOriginParams().commonParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      if (params.persistenceTypeIsExplicit()) {
+        if (NS_WARN_IF(!IsValidPersistenceType(params.persistenceType()))) {
+          MOZ_CRASH_UNLESS_FUZZING();
+          return false;
+        }
+      }
+
+      if (params.clientTypeIsExplicit()) {
+        if (NS_WARN_IF(!Client::IsValidType(params.clientType()))) {
+          MOZ_CRASH_UNLESS_FUZZING();
+          return false;
+        }
+      }
+
+      break;
+    }
+
+    case RequestParams::TResetOriginParams: {
+      const ClearResetOriginParams& params =
+          aParams.get_ResetOriginParams().commonParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      if (params.persistenceTypeIsExplicit()) {
+        if (NS_WARN_IF(!IsValidPersistenceType(params.persistenceType()))) {
+          MOZ_CRASH_UNLESS_FUZZING();
+          return false;
+        }
+      }
+
+      if (params.clientTypeIsExplicit()) {
+        if (NS_WARN_IF(!Client::IsValidType(params.clientType()))) {
+          MOZ_CRASH_UNLESS_FUZZING();
+          return false;
+        }
+      }
+
+      break;
+    }
+
+    case RequestParams::TClearDataParams: {
+      if (BackgroundParent::IsOtherProcessActor(Manager())) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TClearAllParams:
+    case RequestParams::TResetAllParams:
+    case RequestParams::TListOriginsParams:
+      break;
+
+    case RequestParams::TPersistedParams: {
+      const PersistedParams& params = aParams.get_PersistedParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TPersistParams: {
+      const PersistParams& params = aParams.get_PersistParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    case RequestParams::TEstimateParams: {
+      const EstimateParams& params = aParams.get_EstimateParams();
+
+      if (NS_WARN_IF(
+              !QuotaManager::IsPrincipalInfoValid(params.principalInfo()))) {
+        MOZ_CRASH_UNLESS_FUZZING();
+        return false;
+      }
+
+      break;
+    }
+
+    default:
+      MOZ_CRASH("Should never get here!");
+  }
+
+  return true;
+}
+
+void Quota::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnBackgroundThread();
+#ifdef DEBUG
+  MOZ_ASSERT(!mActorDestroyed);
+  mActorDestroyed = true;
+#endif
+}
+
+PQuotaUsageRequestParent* Quota::AllocPQuotaUsageRequestParent(
+    const UsageRequestParams& aParams) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aParams.type() != UsageRequestParams::T__None);
+
+  if (NS_WARN_IF(QuotaManager::IsShuttingDown())) {
+    return nullptr;
+  }
+
+#ifdef DEBUG
+  // Always verify parameters in DEBUG builds!
+  bool trustParams = false;
+#else
+  bool trustParams = !BackgroundParent::IsOtherProcessActor(Manager());
+#endif
+
+  if (!trustParams && NS_WARN_IF(!VerifyRequestParams(aParams))) {
+    MOZ_CRASH_UNLESS_FUZZING();
+    return nullptr;
+  }
+
+  auto actor = [&]() -> RefPtr<QuotaUsageRequestBase> {
+    switch (aParams.type()) {
+      case UsageRequestParams::TAllUsageParams:
+        return MakeRefPtr<GetUsageOp>(aParams);
+
+      case UsageRequestParams::TOriginUsageParams:
+        return MakeRefPtr<GetOriginUsageOp>(aParams);
+
+      default:
+        MOZ_CRASH("Should never get here!");
+    }
+  }();
+
+  MOZ_ASSERT(actor);
+
+  RegisterNormalOriginOp(*actor);
+
+  // Transfer ownership to IPDL.
+  return actor.forget().take();
+}
+
+mozilla::ipc::IPCResult Quota::RecvPQuotaUsageRequestConstructor(
+    PQuotaUsageRequestParent* aActor, const UsageRequestParams& aParams) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aActor);
+  MOZ_ASSERT(aParams.type() != UsageRequestParams::T__None);
+  MOZ_ASSERT(!QuotaManager::IsShuttingDown());
+
+  auto* op = static_cast<QuotaUsageRequestBase*>(aActor);
+
+  op->Init(*this);
+
+  op->RunImmediately();
+  return IPC_OK();
+}
+
+bool Quota::DeallocPQuotaUsageRequestParent(PQuotaUsageRequestParent* aActor) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aActor);
+
+  // Transfer ownership back from IPDL.
+  RefPtr<QuotaUsageRequestBase> actor =
+      dont_AddRef(static_cast<QuotaUsageRequestBase*>(aActor));
+  return true;
+}
+
+PQuotaRequestParent* Quota::AllocPQuotaRequestParent(
+    const RequestParams& aParams) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aParams.type() != RequestParams::T__None);
+
+  if (NS_WARN_IF(QuotaManager::IsShuttingDown())) {
+    return nullptr;
+  }
+
+#ifdef DEBUG
+  // Always verify parameters in DEBUG builds!
+  bool trustParams = false;
+#else
+  bool trustParams = !BackgroundParent::IsOtherProcessActor(Manager());
+#endif
+
+  if (!trustParams && NS_WARN_IF(!VerifyRequestParams(aParams))) {
+    MOZ_CRASH_UNLESS_FUZZING();
+    return nullptr;
+  }
+
+  auto actor = [&]() -> RefPtr<QuotaRequestBase> {
+    switch (aParams.type()) {
+      case RequestParams::TStorageNameParams:
+        return MakeRefPtr<StorageNameOp>();
+
+      case RequestParams::TStorageInitializedParams:
+        return MakeRefPtr<StorageInitializedOp>();
+
+      case RequestParams::TTemporaryStorageInitializedParams:
+        return MakeRefPtr<TemporaryStorageInitializedOp>();
+
+      case RequestParams::TInitParams:
+        return MakeRefPtr<InitOp>();
+
+      case RequestParams::TInitTemporaryStorageParams:
+        return MakeRefPtr<InitTemporaryStorageOp>();
+
+      case RequestParams::TInitializePersistentOriginParams:
+        return MakeRefPtr<InitializePersistentOriginOp>(aParams);
+
+      case RequestParams::TInitializeTemporaryOriginParams:
+        return MakeRefPtr<InitializeTemporaryOriginOp>(aParams);
+
+      case RequestParams::TGetFullOriginMetadataParams:
+        return MakeRefPtr<GetFullOriginMetadataOp>(
+            aParams.get_GetFullOriginMetadataParams());
+
+      case RequestParams::TClearOriginParams:
+        return MakeRefPtr<ClearOriginOp>(aParams);
+
+      case RequestParams::TResetOriginParams:
+        return MakeRefPtr<ResetOriginOp>(aParams);
+
+      case RequestParams::TClearDataParams:
+        return MakeRefPtr<ClearDataOp>(aParams);
+
+      case RequestParams::TClearAllParams:
+        return MakeRefPtr<ResetOrClearOp>(/* aClear */ true);
+
+      case RequestParams::TResetAllParams:
+        return MakeRefPtr<ResetOrClearOp>(/* aClear */ false);
+
+      case RequestParams::TPersistedParams:
+        return MakeRefPtr<PersistedOp>(aParams);
+
+      case RequestParams::TPersistParams:
+        return MakeRefPtr<PersistOp>(aParams);
+
+      case RequestParams::TEstimateParams:
+        return MakeRefPtr<EstimateOp>(aParams.get_EstimateParams());
+
+      case RequestParams::TListOriginsParams:
+        return MakeRefPtr<ListOriginsOp>();
+
+      default:
+        MOZ_CRASH("Should never get here!");
+    }
+  }();
+
+  MOZ_ASSERT(actor);
+
+  RegisterNormalOriginOp(*actor);
+
+  // Transfer ownership to IPDL.
+  return actor.forget().take();
+}
+
+mozilla::ipc::IPCResult Quota::RecvPQuotaRequestConstructor(
+    PQuotaRequestParent* aActor, const RequestParams& aParams) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aActor);
+  MOZ_ASSERT(aParams.type() != RequestParams::T__None);
+  MOZ_ASSERT(!QuotaManager::IsShuttingDown());
+
+  auto* op = static_cast<QuotaRequestBase*>(aActor);
+
+  op->Init(*this);
+
+  op->RunImmediately();
+  return IPC_OK();
+}
+
+bool Quota::DeallocPQuotaRequestParent(PQuotaRequestParent* aActor) {
+  AssertIsOnBackgroundThread();
+  MOZ_ASSERT(aActor);
+
+  // Transfer ownership back from IPDL.
+  RefPtr<QuotaRequestBase> actor =
+      dont_AddRef(static_cast<QuotaRequestBase*>(aActor));
+  return true;
+}
+
+mozilla::ipc::IPCResult Quota::RecvStartIdleMaintenance() {
+  AssertIsOnBackgroundThread();
+
+  PBackgroundParent* actor = Manager();
+  MOZ_ASSERT(actor);
+
+  if (BackgroundParent::IsOtherProcessActor(actor)) {
+    MOZ_CRASH_UNLESS_FUZZING();
+    return IPC_FAIL(this, "Wrong actor");
+  }
+
+  if (QuotaManager::IsShuttingDown()) {
+    return IPC_OK();
+  }
+
+  QM_TRY(QuotaManager::EnsureCreated(), IPC_OK());
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  quotaManager->StartIdleMaintenance();
+
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult Quota::RecvStopIdleMaintenance() {
+  AssertIsOnBackgroundThread();
+
+  PBackgroundParent* actor = Manager();
+  MOZ_ASSERT(actor);
+
+  if (BackgroundParent::IsOtherProcessActor(actor)) {
+    MOZ_CRASH_UNLESS_FUZZING();
+    return IPC_FAIL(this, "Wrong actor");
+  }
+
+  if (QuotaManager::IsShuttingDown()) {
+    return IPC_OK();
+  }
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  if (!quotaManager) {
+    return IPC_OK();
+  }
+
+  quotaManager->StopIdleMaintenance();
+
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult Quota::RecvAbortOperationsForProcess(
+    const ContentParentId& aContentParentId) {
+  AssertIsOnBackgroundThread();
+
+  PBackgroundParent* actor = Manager();
+  MOZ_ASSERT(actor);
+
+  if (BackgroundParent::IsOtherProcessActor(actor)) {
+    MOZ_CRASH_UNLESS_FUZZING();
+    return IPC_FAIL(this, "Wrong actor");
+  }
+
+  if (QuotaManager::IsShuttingDown()) {
+    return IPC_OK();
+  }
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  if (!quotaManager) {
+    return IPC_OK();
+  }
+
+  quotaManager->AbortOperationsForProcess(aContentParentId);
+
+  return IPC_OK();
+}
+
+void QuotaUsageRequestBase::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = true;
+}
+
+Result<UsageInfo, nsresult> QuotaUsageRequestBase::GetUsageForOrigin(
+    QuotaManager& aQuotaManager, PersistenceType aPersistenceType,
+    const OriginMetadata& aOriginMetadata) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& directory,
+                 aQuotaManager.GetDirectoryForOrigin(aPersistenceType,
+                                                     aOriginMetadata.mOrigin));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists));
+
+  if (!exists || mCanceled) {
+    return UsageInfo();
+  }
+
+  // If the directory exists then enumerate all the files inside, adding up
+  // the sizes to get the final usage statistic.
+  bool initialized;
+
+  if (aPersistenceType == PERSISTENCE_TYPE_PERSISTENT) {
+    initialized = aQuotaManager.IsOriginInitialized(aOriginMetadata.mOrigin);
+  } else {
+    initialized = aQuotaManager.IsTemporaryStorageInitialized();
+  }
+
+  return GetUsageForOriginEntries(aQuotaManager, aPersistenceType,
+                                  aOriginMetadata, *directory, initialized);
+}
+
+Result<UsageInfo, nsresult> QuotaUsageRequestBase::GetUsageForOriginEntries(
+    QuotaManager& aQuotaManager, PersistenceType aPersistenceType,
+    const OriginMetadata& aOriginMetadata, nsIFile& aDirectory,
+    const bool aInitialized) {
+  AssertIsOnIOThread();
+
+  QM_TRY_RETURN((ReduceEachFileAtomicCancelable(
+      aDirectory, mCanceled, UsageInfo{},
+      [&](UsageInfo oldUsageInfo, const nsCOMPtr<nsIFile>& file)
+          -> mozilla::Result<UsageInfo, nsresult> {
+        QM_TRY_INSPECT(
+            const auto& leafName,
+            MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, file, GetLeafName));
+
+        QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*file));
+
+        switch (dirEntryKind) {
+          case nsIFileKind::ExistsAsDirectory: {
+            Client::Type clientType;
+            const bool ok =
+                Client::TypeFromText(leafName, clientType, fallible);
+            if (!ok) {
+              // Unknown directories during getting usage for an origin (even
+              // for an uninitialized origin) are now allowed. Just warn if we
+              // find them.
+              UNKNOWN_FILE_WARNING(leafName);
+              break;
+            }
+
+            Client* const client = aQuotaManager.GetClient(clientType);
+            MOZ_ASSERT(client);
+
+            QM_TRY_INSPECT(
+                const auto& usageInfo,
+                aInitialized ? client->GetUsageForOrigin(
+                                   aPersistenceType, aOriginMetadata, mCanceled)
+                             : client->InitOrigin(aPersistenceType,
+                                                  aOriginMetadata, mCanceled));
+            return oldUsageInfo + usageInfo;
+          }
+
+          case nsIFileKind::ExistsAsFile:
+            // We are maintaining existing behavior for unknown files here (just
+            // continuing).
+            // This can possibly be used by developers to add temporary backups
+            // into origin directories without losing get usage functionality.
+            if (IsTempMetadata(leafName)) {
+              if (!aInitialized) {
+                QM_TRY(MOZ_TO_RESULT(file->Remove(/* recursive */ false)));
+              }
+
+              break;
+            }
+
+            if (IsOriginMetadata(leafName) || IsOSMetadata(leafName) ||
+                IsDotFile(leafName)) {
+              break;
+            }
+
+            // Unknown files during getting usage for an origin (even for an
+            // uninitialized origin) are now allowed. Just warn if we find them.
+            UNKNOWN_FILE_WARNING(leafName);
+            break;
+
+          case nsIFileKind::DoesNotExist:
+            // Ignore files that got removed externally while iterating.
+            break;
+        }
+
+        return oldUsageInfo;
+      })));
+}
+
+void QuotaUsageRequestBase::SendResults() {
+  AssertIsOnOwningThread();
+
+  if (IsActorDestroyed()) {
+    if (NS_SUCCEEDED(mResultCode)) {
+      mResultCode = NS_ERROR_FAILURE;
+    }
+  } else {
+    if (mCanceled) {
+      mResultCode = NS_ERROR_FAILURE;
+    }
+
+    UsageRequestResponse response;
+
+    if (NS_SUCCEEDED(mResultCode)) {
+      GetResponse(response);
+    } else {
+      response = mResultCode;
+    }
+
+    Unused << PQuotaUsageRequestParent::Send__delete__(this, response);
+  }
+}
+
+void QuotaUsageRequestBase::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnOwningThread();
+
+  NoteActorDestroyed();
+}
+
+mozilla::ipc::IPCResult QuotaUsageRequestBase::RecvCancel() {
+  AssertIsOnOwningThread();
+
+  if (mCanceled.exchange(true)) {
+    NS_WARNING("Canceled more than once?!");
+    return IPC_FAIL(this, "Request canceled more than once");
+  }
+
+  return IPC_OK();
+}
+
+nsresult TraverseRepositoryHelper::TraverseRepository(
+    QuotaManager& aQuotaManager, PersistenceType aPersistenceType) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(
+      const auto& directory,
+      QM_NewLocalFile(aQuotaManager.GetStoragePath(aPersistenceType)));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists));
+
+  if (!exists) {
+    return NS_OK;
+  }
+
+  QM_TRY(CollectEachFileAtomicCancelable(
+      *directory, GetIsCanceledFlag(),
+      [this, aPersistenceType, &aQuotaManager,
+       persistent = aPersistenceType == PERSISTENCE_TYPE_PERSISTENT](
+          const nsCOMPtr<nsIFile>& originDir) -> Result<Ok, nsresult> {
+        QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*originDir));
+
+        switch (dirEntryKind) {
+          case nsIFileKind::ExistsAsDirectory:
+            QM_TRY(MOZ_TO_RESULT(ProcessOrigin(aQuotaManager, *originDir,
+                                               persistent, aPersistenceType)));
+            break;
+
+          case nsIFileKind::ExistsAsFile: {
+            QM_TRY_INSPECT(const auto& leafName,
+                           MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                               nsAutoString, originDir, GetLeafName));
+
+            // Unknown files during getting usages are allowed. Just warn if we
+            // find them.
+            if (!IsOSMetadata(leafName)) {
+              UNKNOWN_FILE_WARNING(leafName);
+            }
+
+            break;
+          }
+
+          case nsIFileKind::DoesNotExist:
+            // Ignore files that got removed externally while iterating.
+            break;
+        }
+
+        return Ok{};
+      }));
+
+  return NS_OK;
+}
+
+GetUsageOp::GetUsageOp(const UsageRequestParams& aParams)
+    : QuotaUsageRequestBase("dom::quota::GetUsageOp"),
+      mGetAll(aParams.get_AllUsageParams().getAll()) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aParams.type() == UsageRequestParams::TAllUsageParams);
+}
+
+void GetUsageOp::ProcessOriginInternal(QuotaManager* aQuotaManager,
+                                       const PersistenceType aPersistenceType,
+                                       const nsACString& aOrigin,
+                                       const int64_t aTimestamp,
+                                       const bool aPersisted,
+                                       const uint64_t aUsage) {
+  if (!mGetAll && aQuotaManager->IsOriginInternal(aOrigin)) {
+    return;
+  }
+
+  // We can't store pointers to OriginUsage objects in the hashtable
+  // since AppendElement() reallocates its internal array buffer as number
+  // of elements grows.
+  const auto& originUsage =
+      mOriginUsagesIndex.WithEntryHandle(aOrigin, [&](auto&& entry) {
+        if (entry) {
+          return WrapNotNullUnchecked(&mOriginUsages[entry.Data()]);
+        }
+
+        entry.Insert(mOriginUsages.Length());
+
+        return mOriginUsages.EmplaceBack(nsCString{aOrigin}, false, 0, 0);
+      });
+
+  if (aPersistenceType == PERSISTENCE_TYPE_DEFAULT) {
+    originUsage->persisted() = aPersisted;
+  }
+
+  originUsage->usage() = originUsage->usage() + aUsage;
+
+  originUsage->lastAccessed() =
+      std::max<int64_t>(originUsage->lastAccessed(), aTimestamp);
+}
+
+const Atomic<bool>& GetUsageOp::GetIsCanceledFlag() {
+  AssertIsOnIOThread();
+
+  return mCanceled;
+}
+
+// XXX Remove aPersistent
+// XXX Remove aPersistenceType once GetUsageForOrigin uses the persistence
+// type from OriginMetadata
+nsresult GetUsageOp::ProcessOrigin(QuotaManager& aQuotaManager,
+                                   nsIFile& aOriginDir, const bool aPersistent,
+                                   const PersistenceType aPersistenceType) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& metadata,
+                 aQuotaManager.LoadFullOriginMetadataWithRestore(&aOriginDir));
+
+  QM_TRY_INSPECT(const auto& usageInfo,
+                 GetUsageForOrigin(aQuotaManager, aPersistenceType, metadata));
+
+  ProcessOriginInternal(&aQuotaManager, aPersistenceType, metadata.mOrigin,
+                        metadata.mLastAccessTime, metadata.mPersisted,
+                        usageInfo.TotalUsage().valueOr(0));
+
+  return NS_OK;
+}
+
+nsresult GetUsageOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+
+  AUTO_PROFILER_LABEL("GetUsageOp::DoDirectoryWork", OTHER);
+
+  nsresult rv;
+
+  for (const PersistenceType type : kAllPersistenceTypes) {
+    rv = TraverseRepository(aQuotaManager, type);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+  }
+
+  // TraverseRepository above only consulted the filesystem. We also need to
+  // consider origins which may have pending quota usage, such as buffered
+  // LocalStorage writes for an origin which didn't previously have any
+  // LocalStorage data.
+
+  aQuotaManager.CollectPendingOriginsForListing(
+      [this, &aQuotaManager](const auto& originInfo) {
+        ProcessOriginInternal(
+            &aQuotaManager, originInfo->GetGroupInfo()->GetPersistenceType(),
+            originInfo->Origin(), originInfo->LockedAccessTime(),
+            originInfo->LockedPersisted(), originInfo->LockedUsage());
+      });
+
+  return NS_OK;
+}
+
+void GetUsageOp::GetResponse(UsageRequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = AllUsageResponse();
+
+  aResponse.get_AllUsageResponse().originUsages() = std::move(mOriginUsages);
+}
+
+GetOriginUsageOp::GetOriginUsageOp(const UsageRequestParams& aParams)
+    : QuotaUsageRequestBase("dom::quota::GetOriginUsageOp"),
+      mUsage(0),
+      mFileUsage(0) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aParams.type() == UsageRequestParams::TOriginUsageParams);
+
+  const OriginUsageParams& params = aParams.get_OriginUsageParams();
+
+  PrincipalMetadata principalMetadata =
+      QuotaManager::GetInfoFromValidatedPrincipalInfo(params.principalInfo());
+
+  mSuffix = std::move(principalMetadata.mSuffix);
+  mGroup = std::move(principalMetadata.mGroup);
+  mOriginScope.SetFromOrigin(principalMetadata.mOrigin);
+
+  mFromMemory = params.fromMemory();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = true;
+}
+
+RefPtr<DirectoryLock> GetOriginUsageOp::CreateDirectoryLock() {
+  if (mFromMemory) {
+    return nullptr;
+  }
+
+  return QuotaUsageRequestBase::CreateDirectoryLock();
+}
+
+nsresult GetOriginUsageOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+  MOZ_ASSERT(mUsage == 0);
+  MOZ_ASSERT(mFileUsage == 0);
+
+  AUTO_PROFILER_LABEL("GetOriginUsageOp::DoDirectoryWork", OTHER);
+
+  if (mFromMemory) {
+    const PrincipalMetadata principalMetadata = {
+        mSuffix, mGroup, nsCString{mOriginScope.GetOrigin()}};
+
+    // Ensure temporary storage is initialized. If temporary storage hasn't been
+    // initialized yet, the method will initialize it by traversing the
+    // repositories for temporary and default storage (including our origin).
+    QM_TRY(MOZ_TO_RESULT(aQuotaManager.EnsureTemporaryStorageIsInitialized()));
+
+    // Get cached usage (the method doesn't have to stat any files). File usage
+    // is not tracked in memory separately, so just add to the total usage.
+    mUsage = aQuotaManager.GetOriginUsage(principalMetadata);
+
+    return NS_OK;
+  }
+
+  UsageInfo usageInfo;
+
+  // Add all the persistent/temporary/default storage files we care about.
+  for (const PersistenceType type : kAllPersistenceTypes) {
+    const OriginMetadata originMetadata = {
+        mSuffix, mGroup, nsCString{mOriginScope.GetOrigin()}, type};
+
+    auto usageInfoOrErr =
+        GetUsageForOrigin(aQuotaManager, type, originMetadata);
+    if (NS_WARN_IF(usageInfoOrErr.isErr())) {
+      return usageInfoOrErr.unwrapErr();
+    }
+
+    usageInfo += usageInfoOrErr.unwrap();
+  }
+
+  mUsage = usageInfo.TotalUsage().valueOr(0);
+  mFileUsage = usageInfo.FileUsage().valueOr(0);
+
+  return NS_OK;
+}
+
+void GetOriginUsageOp::GetResponse(UsageRequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  OriginUsageResponse usageResponse;
+
+  usageResponse.usage() = mUsage;
+  usageResponse.fileUsage() = mFileUsage;
+
+  aResponse = usageResponse;
+}
+
+void QuotaRequestBase::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = true;
+}
+
+void QuotaRequestBase::SendResults() {
+  AssertIsOnOwningThread();
+
+  if (IsActorDestroyed()) {
+    if (NS_SUCCEEDED(mResultCode)) {
+      mResultCode = NS_ERROR_FAILURE;
+    }
+  } else {
+    RequestResponse response;
+
+    if (NS_SUCCEEDED(mResultCode)) {
+      GetResponse(response);
+    } else {
+      response = mResultCode;
+    }
+
+    Unused << PQuotaRequestParent::Send__delete__(this, response);
+  }
+}
+
+void QuotaRequestBase::ActorDestroy(ActorDestroyReason aWhy) {
+  AssertIsOnOwningThread();
+
+  NoteActorDestroyed();
+}
+
+StorageNameOp::StorageNameOp()
+    : QuotaRequestBase("dom::quota::StorageNameOp", /* aExclusive */ false) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+}
+
+void StorageNameOp::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+RefPtr<DirectoryLock> StorageNameOp::CreateDirectoryLock() { return nullptr; }
+
+nsresult StorageNameOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("StorageNameOp::DoDirectoryWork", OTHER);
+
+  mName = aQuotaManager.GetStorageName();
+
+  return NS_OK;
+}
+
+void StorageNameOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  StorageNameResponse storageNameResponse;
+
+  storageNameResponse.name() = mName;
+
+  aResponse = storageNameResponse;
+}
+
+InitializedRequestBase::InitializedRequestBase(const char* aRunnableName)
+    : QuotaRequestBase(aRunnableName, /* aExclusive */ false),
+      mInitialized(false) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+}
+
+void InitializedRequestBase::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+RefPtr<DirectoryLock> InitializedRequestBase::CreateDirectoryLock() {
+  return nullptr;
+}
+
+nsresult StorageInitializedOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("StorageInitializedOp::DoDirectoryWork", OTHER);
+
+  mInitialized = aQuotaManager.IsStorageInitialized();
+
+  return NS_OK;
+}
+
+void StorageInitializedOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  StorageInitializedResponse storageInitializedResponse;
+
+  storageInitializedResponse.initialized() = mInitialized;
+
+  aResponse = storageInitializedResponse;
+}
+
+nsresult TemporaryStorageInitializedOp::DoDirectoryWork(
+    QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("TemporaryStorageInitializedOp::DoDirectoryWork", OTHER);
+
+  mInitialized = aQuotaManager.IsTemporaryStorageInitialized();
+
+  return NS_OK;
+}
+
+void TemporaryStorageInitializedOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  TemporaryStorageInitializedResponse temporaryStorageInitializedResponse;
+
+  temporaryStorageInitializedResponse.initialized() = mInitialized;
+
+  aResponse = temporaryStorageInitializedResponse;
+}
+
+InitOp::InitOp()
+    : QuotaRequestBase("dom::quota::InitOp", /* aExclusive */ false) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+}
+
+void InitOp::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+nsresult InitOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("InitOp::DoDirectoryWork", OTHER);
+
+  QM_TRY(MOZ_TO_RESULT(aQuotaManager.EnsureStorageIsInitialized()));
+
+  return NS_OK;
+}
+
+void InitOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = InitResponse();
+}
+
+InitTemporaryStorageOp::InitTemporaryStorageOp()
+    : QuotaRequestBase("dom::quota::InitTemporaryStorageOp",
+                       /* aExclusive */ false) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+}
+
+void InitTemporaryStorageOp::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+nsresult InitTemporaryStorageOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("InitTemporaryStorageOp::DoDirectoryWork", OTHER);
+
+  QM_TRY(OkIf(aQuotaManager.IsStorageInitialized()), NS_ERROR_FAILURE);
+
+  QM_TRY(MOZ_TO_RESULT(aQuotaManager.EnsureTemporaryStorageIsInitialized()));
+
+  return NS_OK;
+}
+
+void InitTemporaryStorageOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = InitTemporaryStorageResponse();
+}
+
+InitializeOriginRequestBase::InitializeOriginRequestBase(
+    const char* aRunnableName, const PersistenceType aPersistenceType,
+    const PrincipalInfo& aPrincipalInfo)
+    : QuotaRequestBase(aRunnableName,
+                       /* aExclusive */ false),
+      mCreated(false) {
+  AssertIsOnOwningThread();
+
+  auto principalMetadata =
+      QuotaManager::GetInfoFromValidatedPrincipalInfo(aPrincipalInfo);
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+
+  // Overwrite NormalOriginOperationBase default values.
+  mPersistenceType.SetValue(aPersistenceType);
+  mOriginScope.SetFromOrigin(principalMetadata.mOrigin);
+
+  // Overwrite InitializeOriginRequestBase default values.
+  mSuffix = std::move(principalMetadata.mSuffix);
+  mGroup = std::move(principalMetadata.mGroup);
+}
+
+void InitializeOriginRequestBase::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+}
+
+InitializePersistentOriginOp::InitializePersistentOriginOp(
+    const RequestParams& aParams)
+    : InitializeOriginRequestBase(
+          "dom::quota::InitializePersistentOriginOp",
+          PERSISTENCE_TYPE_PERSISTENT,
+          aParams.get_InitializePersistentOriginParams().principalInfo()) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aParams.type() ==
+             RequestParams::TInitializePersistentOriginParams);
+}
+
+nsresult InitializePersistentOriginOp::DoDirectoryWork(
+    QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!mPersistenceType.IsNull());
+
+  AUTO_PROFILER_LABEL("InitializePersistentOriginOp::DoDirectoryWork", OTHER);
+
+  QM_TRY(OkIf(aQuotaManager.IsStorageInitialized()), NS_ERROR_FAILURE);
+
+  QM_TRY_UNWRAP(mCreated,
+                (aQuotaManager
+                     .EnsurePersistentOriginIsInitialized(OriginMetadata{
+                         mSuffix, mGroup, nsCString{mOriginScope.GetOrigin()},
+                         PERSISTENCE_TYPE_PERSISTENT})
+                     .map([](const auto& res) { return res.second; })));
+
+  return NS_OK;
+}
+
+void InitializePersistentOriginOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = InitializePersistentOriginResponse(mCreated);
+}
+
+InitializeTemporaryOriginOp::InitializeTemporaryOriginOp(
+    const RequestParams& aParams)
+    : InitializeOriginRequestBase(
+          "dom::quota::InitializeTemporaryOriginOp",
+          aParams.get_InitializeTemporaryOriginParams().persistenceType(),
+          aParams.get_InitializeTemporaryOriginParams().principalInfo()) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aParams.type() == RequestParams::TInitializeTemporaryOriginParams);
+}
+
+nsresult InitializeTemporaryOriginOp::DoDirectoryWork(
+    QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!mPersistenceType.IsNull());
+
+  AUTO_PROFILER_LABEL("InitializeTemporaryOriginOp::DoDirectoryWork", OTHER);
+
+  QM_TRY(OkIf(aQuotaManager.IsStorageInitialized()), NS_ERROR_FAILURE);
+
+  QM_TRY(OkIf(aQuotaManager.IsTemporaryStorageInitialized()), NS_ERROR_FAILURE);
+
+  QM_TRY_UNWRAP(mCreated,
+                (aQuotaManager
+                     .EnsureTemporaryOriginIsInitialized(
+                         mPersistenceType.Value(),
+                         OriginMetadata{mSuffix, mGroup,
+                                        nsCString{mOriginScope.GetOrigin()},
+                                        mPersistenceType.Value()})
+                     .map([](const auto& res) { return res.second; })));
+
+  return NS_OK;
+}
+
+void InitializeTemporaryOriginOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = InitializeTemporaryOriginResponse(mCreated);
+}
+
+GetFullOriginMetadataOp::GetFullOriginMetadataOp(
+    const GetFullOriginMetadataParams& aParams)
+    : QuotaRequestBase("dom::quota::GetFullOriginMetadataOp",
+                       /* aExclusive */ false),
+      mOriginMetadata(QuotaManager::GetInfoFromValidatedPrincipalInfo(
+                          aParams.principalInfo()),
+                      aParams.persistenceType()) {
+  AssertIsOnOwningThread();
+}
+
+RefPtr<DirectoryLock> GetFullOriginMetadataOp::CreateDirectoryLock() {
+  return nullptr;
+}
+
+nsresult GetFullOriginMetadataOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("GetFullOriginMetadataOp::DoDirectoryWork", OTHER);
+
+  // Ensure temporary storage is initialized. If temporary storage hasn't
+  // been initialized yet, the method will initialize it by traversing the
+  // repositories for temporary and default storage (including our origin).
+  QM_TRY(MOZ_TO_RESULT(aQuotaManager.EnsureTemporaryStorageIsInitialized()));
+
+  // Get metadata cached in memory (the method doesn't have to stat any
+  // files).
+  mMaybeFullOriginMetadata =
+      aQuotaManager.GetFullOriginMetadata(mOriginMetadata);
+
+  return NS_OK;
+}
+
+void GetFullOriginMetadataOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = GetFullOriginMetadataResponse();
+  aResponse.get_GetFullOriginMetadataResponse().maybeFullOriginMetadata() =
+      std::move(mMaybeFullOriginMetadata);
+}
+
+ResetOrClearOp::ResetOrClearOp(bool aClear)
+    : QuotaRequestBase("dom::quota::ResetOrClearOp", /* aExclusive */ true),
+      mClear(aClear) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+}
+
+void ResetOrClearOp::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+void ResetOrClearOp::DeleteFiles(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  nsresult rv = aQuotaManager.AboutToClearOrigins(Nullable<PersistenceType>(),
+                                                  OriginScope::FromNull(),
+                                                  Nullable<Client::Type>());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+
+  auto directoryOrErr = QM_NewLocalFile(aQuotaManager.GetStoragePath());
+  if (NS_WARN_IF(directoryOrErr.isErr())) {
+    return;
+  }
+
+  nsCOMPtr<nsIFile> directory = directoryOrErr.unwrap();
+
+  rv = directory->Remove(true);
+  if (rv != NS_ERROR_FILE_NOT_FOUND && NS_FAILED(rv)) {
+    // This should never fail if we've closed all storage connections
+    // correctly...
+    MOZ_ASSERT(false, "Failed to remove storage directory!");
+  }
+}
+
+void ResetOrClearOp::DeleteStorageFile(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& storageFile,
+                 QM_NewLocalFile(aQuotaManager.GetBasePath()), QM_VOID);
+
+  QM_TRY(MOZ_TO_RESULT(storageFile->Append(aQuotaManager.GetStorageName() +
+                                           kSQLiteSuffix)),
+         QM_VOID);
+
+  const nsresult rv = storageFile->Remove(true);
+  if (rv != NS_ERROR_FILE_NOT_FOUND && NS_FAILED(rv)) {
+    // This should never fail if we've closed the storage connection
+    // correctly...
+    MOZ_ASSERT(false, "Failed to remove storage file!");
+  }
+}
+
+nsresult ResetOrClearOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("ResetOrClearOp::DoDirectoryWork", OTHER);
+
+  if (mClear) {
+    DeleteFiles(aQuotaManager);
+
+    aQuotaManager.RemoveQuota();
+  }
+
+  aQuotaManager.ShutdownStorageInternal();
+
+  if (mClear) {
+    DeleteStorageFile(aQuotaManager);
+  }
+
+  return NS_OK;
+}
+
+void ResetOrClearOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+  if (mClear) {
+    aResponse = ClearAllResponse();
+  } else {
+    aResponse = ResetAllResponse();
+  }
+}
+
+static Result<nsCOMPtr<nsIFile>, QMResult> OpenToBeRemovedDirectory(
+    const nsAString& aStoragePath) {
+  QM_TRY_INSPECT(const auto& dir,
+                 QM_TO_RESULT_TRANSFORM(QM_NewLocalFile(aStoragePath)));
+  QM_TRY(QM_TO_RESULT(dir->Append(u"to-be-removed"_ns)));
+
+  nsresult rv = dir->Create(nsIFile::DIRECTORY_TYPE, 0700);
+  if (NS_SUCCEEDED(rv) || rv == NS_ERROR_FILE_ALREADY_EXISTS) {
+    return dir;
+  }
+  return Err(QMResult(rv));
+}
+
+static Result<Ok, QMResult> RemoveOrMoveToDir(nsIFile& aFile,
+                                              nsIFile* aMoveTargetDir) {
+  if (!aMoveTargetDir) {
+    QM_TRY(QM_TO_RESULT(aFile.Remove(true)));
+    return Ok();
+  }
+
+  nsIDToCString uuid(nsID::GenerateUUID());
+  NS_ConvertUTF8toUTF16 subDirName(uuid.get(), NSID_LENGTH - 1);
+  QM_TRY(QM_TO_RESULT(aFile.MoveTo(aMoveTargetDir, subDirName)));
+  return Ok();
+}
+
+void ClearRequestBase::DeleteFiles(QuotaManager& aQuotaManager,
+                                   PersistenceType aPersistenceType) {
+  AssertIsOnIOThread();
+
+  QM_TRY(MOZ_TO_RESULT(aQuotaManager.AboutToClearOrigins(
+             Nullable<PersistenceType>(aPersistenceType), mOriginScope,
+             mClientType)),
+         QM_VOID);
+
+  QM_TRY_INSPECT(
+      const auto& directory,
+      QM_NewLocalFile(aQuotaManager.GetStoragePath(aPersistenceType)), QM_VOID);
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists), QM_VOID);
+
+  if (!exists) {
+    return;
+  }
+
+  nsTArray<nsCOMPtr<nsIFile>> directoriesForRemovalRetry;
+
+  aQuotaManager.MaybeRecordQuotaManagerShutdownStep(
+      "ClearRequestBase: Starting deleting files"_ns);
+  nsCOMPtr<nsIFile> toBeRemovedDir;
+  if (AppShutdown::IsInOrBeyond(ShutdownPhase::AppShutdownTeardown)) {
+    QM_WARNONLY_TRY_UNWRAP(
+        auto result, OpenToBeRemovedDirectory(aQuotaManager.GetStoragePath()));
+    toBeRemovedDir = result.valueOr(nullptr);
+  }
+  QM_TRY(
+      CollectEachFile(
+          *directory,
+          [originScope =
+               [this] {
+                 OriginScope originScope = mOriginScope.Clone();
+                 if (originScope.IsOrigin()) {
+                   originScope.SetOrigin(
+                       MakeSanitizedOriginCString(originScope.GetOrigin()));
+                 } else if (originScope.IsPrefix()) {
+                   originScope.SetOriginNoSuffix(MakeSanitizedOriginCString(
+                       originScope.GetOriginNoSuffix()));
+                 }
+                 return originScope;
+               }(),
+           aPersistenceType, &aQuotaManager, &directoriesForRemovalRetry,
+           &toBeRemovedDir,
+           this](nsCOMPtr<nsIFile>&& file) -> mozilla::Result<Ok, nsresult> {
+            QM_TRY_INSPECT(const auto& leafName,
+                           MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, file,
+                                                             GetLeafName));
+
+            QM_TRY_INSPECT(const auto& dirEntryKind, GetDirEntryKind(*file));
+
+            switch (dirEntryKind) {
+              case nsIFileKind::ExistsAsDirectory: {
+                // Skip the origin directory if it doesn't match the pattern.
+                if (!originScope.Matches(OriginScope::FromOrigin(
+                        NS_ConvertUTF16toUTF8(leafName)))) {
+                  break;
+                }
+
+                QM_TRY_INSPECT(
+                    const auto& metadata,
+                    aQuotaManager.LoadFullOriginMetadataWithRestore(file));
+
+                MOZ_ASSERT(metadata.mPersistenceType == aPersistenceType);
+
+                if (!mClientType.IsNull()) {
+                  nsAutoString clientDirectoryName;
+                  QM_TRY(
+                      OkIf(Client::TypeToText(mClientType.Value(),
+                                              clientDirectoryName, fallible)),
+                      Err(NS_ERROR_FAILURE));
+
+                  QM_TRY(MOZ_TO_RESULT(file->Append(clientDirectoryName)));
+
+                  QM_TRY_INSPECT(const bool& exists,
+                                 MOZ_TO_RESULT_INVOKE_MEMBER(file, Exists));
+
+                  if (!exists) {
+                    break;
+                  }
+                }
+
+                // We can't guarantee that this will always succeed on
+                // Windows...
+                QM_WARNONLY_TRY(
+                    RemoveOrMoveToDir(*file, toBeRemovedDir), [&](const auto&) {
+                      directoriesForRemovalRetry.AppendElement(std::move(file));
+                    });
+
+                const bool initialized =
+                    aPersistenceType == PERSISTENCE_TYPE_PERSISTENT
+                        ? aQuotaManager.IsOriginInitialized(metadata.mOrigin)
+                        : aQuotaManager.IsTemporaryStorageInitialized();
+
+                // If it hasn't been initialized, we don't need to update the
+                // quota and notify the removing client.
+                if (!initialized) {
+                  break;
+                }
+
+                if (aPersistenceType != PERSISTENCE_TYPE_PERSISTENT) {
+                  if (mClientType.IsNull()) {
+                    aQuotaManager.RemoveQuotaForOrigin(aPersistenceType,
+                                                       metadata);
+                  } else {
+                    aQuotaManager.ResetUsageForClient(
+                        ClientMetadata{metadata, mClientType.Value()});
+                  }
+                }
+
+                aQuotaManager.OriginClearCompleted(
+                    aPersistenceType, metadata.mOrigin, mClientType);
+
+                break;
+              }
+
+              case nsIFileKind::ExistsAsFile:
+                // Unknown files during clearing are allowed. Just warn if we
+                // find them.
+                if (!IsOSMetadata(leafName)) {
+                  UNKNOWN_FILE_WARNING(leafName);
+                }
+
+                break;
+
+              case nsIFileKind::DoesNotExist:
+                // Ignore files that got removed externally while iterating.
+                break;
+            }
+
+            return Ok{};
+          }),
+      QM_VOID);
+
+  // Retry removing any directories that failed to be removed earlier now.
+  //
+  // XXX This will still block this operation. We might instead dispatch a
+  // runnable to our own thread for each retry round with a timer. We must
+  // ensure that the directory lock is upheld until we complete or give up
+  // though.
+  for (uint32_t index = 0; index < 10; index++) {
+    aQuotaManager.MaybeRecordQuotaManagerShutdownStepWith([index]() {
+      return nsPrintfCString(
+          "ClearRequestBase: Starting repeated directory removal #%d", index);
+    });
+
+    for (auto&& file : std::exchange(directoriesForRemovalRetry,
+                                     nsTArray<nsCOMPtr<nsIFile>>{})) {
+      QM_WARNONLY_TRY(
+          QM_TO_RESULT(file->Remove(true)),
+          ([&directoriesForRemovalRetry, &file](const auto&) {
+            directoriesForRemovalRetry.AppendElement(std::move(file));
+          }));
+    }
+
+    aQuotaManager.MaybeRecordQuotaManagerShutdownStepWith([index]() {
+      return nsPrintfCString(
+          "ClearRequestBase: Completed repeated directory removal #%d", index);
+    });
+
+    if (directoriesForRemovalRetry.IsEmpty()) {
+      break;
+    }
+
+    aQuotaManager.MaybeRecordQuotaManagerShutdownStepWith([index]() {
+      return nsPrintfCString("ClearRequestBase: Before sleep #%d", index);
+    });
+
+    PR_Sleep(PR_MillisecondsToInterval(200));
+
+    aQuotaManager.MaybeRecordQuotaManagerShutdownStepWith([index]() {
+      return nsPrintfCString("ClearRequestBase: After sleep #%d", index);
+    });
+  }
+
+  QM_WARNONLY_TRY(OkIf(directoriesForRemovalRetry.IsEmpty()));
+
+  aQuotaManager.MaybeRecordQuotaManagerShutdownStep(
+      "ClearRequestBase: Completed deleting files"_ns);
+}
+
+nsresult ClearRequestBase::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+
+  AUTO_PROFILER_LABEL("ClearRequestBase::DoDirectoryWork", OTHER);
+
+  if (mPersistenceType.IsNull()) {
+    for (const PersistenceType type : kAllPersistenceTypes) {
+      DeleteFiles(aQuotaManager, type);
+    }
+  } else {
+    DeleteFiles(aQuotaManager, mPersistenceType.Value());
+  }
+
+  return NS_OK;
+}
+
+ClearOriginOp::ClearOriginOp(const RequestParams& aParams)
+    : ClearRequestBase("dom::quota::ClearOriginOp", /* aExclusive */ true),
+      mParams(aParams.get_ClearOriginParams().commonParams()),
+      mMatchAll(aParams.get_ClearOriginParams().matchAll()) {
+  MOZ_ASSERT(aParams.type() == RequestParams::TClearOriginParams);
+}
+
+void ClearOriginOp::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  QuotaRequestBase::Init(aQuota);
+
+  if (mParams.persistenceTypeIsExplicit()) {
+    mPersistenceType.SetValue(mParams.persistenceType());
+  }
+
+  // Figure out which origin we're dealing with.
+  const auto origin = QuotaManager::GetOriginFromValidatedPrincipalInfo(
+      mParams.principalInfo());
+
+  if (mMatchAll) {
+    mOriginScope.SetFromPrefix(origin);
+  } else {
+    mOriginScope.SetFromOrigin(origin);
+  }
+
+  if (mParams.clientTypeIsExplicit()) {
+    mClientType.SetValue(mParams.clientType());
+  }
+}
+
+void ClearOriginOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = ClearOriginResponse();
+}
+
+ClearDataOp::ClearDataOp(const RequestParams& aParams)
+    : ClearRequestBase("dom::quota::ClearDataOp", /* aExclusive */ true),
+      mParams(aParams) {
+  MOZ_ASSERT(aParams.type() == RequestParams::TClearDataParams);
+}
+
+void ClearDataOp::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  QuotaRequestBase::Init(aQuota);
+
+  mOriginScope.SetFromPattern(mParams.pattern());
+}
+
+void ClearDataOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = ClearDataResponse();
+}
+
+ResetOriginOp::ResetOriginOp(const RequestParams& aParams)
+    : QuotaRequestBase("dom::quota::ResetOriginOp", /* aExclusive */ true) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aParams.type() == RequestParams::TResetOriginParams);
+
+  const ClearResetOriginParams& params =
+      aParams.get_ResetOriginParams().commonParams();
+
+  const auto origin =
+      QuotaManager::GetOriginFromValidatedPrincipalInfo(params.principalInfo());
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = false;
+
+  // Overwrite NormalOriginOperationBase default values.
+  if (params.persistenceTypeIsExplicit()) {
+    mPersistenceType.SetValue(params.persistenceType());
+  }
+
+  mOriginScope.SetFromOrigin(origin);
+
+  if (params.clientTypeIsExplicit()) {
+    mClientType.SetValue(params.clientType());
+  }
+}
+
+void ResetOriginOp::Init(Quota& aQuota) { AssertIsOnOwningThread(); }
+
+nsresult ResetOriginOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+
+  AUTO_PROFILER_LABEL("ResetOriginOp::DoDirectoryWork", OTHER);
+
+  // All the work is handled by NormalOriginOperationBase parent class. In this
+  // particular case, we just needed to acquire an exclusive directory lock and
+  // that's it.
+
+  return NS_OK;
+}
+
+void ResetOriginOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = ResetOriginResponse();
+}
+
+PersistRequestBase::PersistRequestBase(const PrincipalInfo& aPrincipalInfo)
+    : QuotaRequestBase("dom::quota::PersistRequestBase",
+                       /* aExclusive */ false),
+      mPrincipalInfo(aPrincipalInfo) {
+  AssertIsOnOwningThread();
+}
+
+void PersistRequestBase::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  QuotaRequestBase::Init(aQuota);
+
+  mPersistenceType.SetValue(PERSISTENCE_TYPE_DEFAULT);
+
+  // Figure out which origin we're dealing with.
+  PrincipalMetadata principalMetadata =
+      QuotaManager::GetInfoFromValidatedPrincipalInfo(mPrincipalInfo);
+
+  mSuffix = std::move(principalMetadata.mSuffix);
+  mGroup = std::move(principalMetadata.mGroup);
+  mOriginScope.SetFromOrigin(principalMetadata.mOrigin);
+}
+
+PersistedOp::PersistedOp(const RequestParams& aParams)
+    : PersistRequestBase(aParams.get_PersistedParams().principalInfo()),
+      mPersisted(false) {
+  MOZ_ASSERT(aParams.type() == RequestParams::TPersistedParams);
+}
+
+nsresult PersistedOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+  MOZ_ASSERT(!mPersistenceType.IsNull());
+  MOZ_ASSERT(mPersistenceType.Value() == PERSISTENCE_TYPE_DEFAULT);
+  MOZ_ASSERT(mOriginScope.IsOrigin());
+
+  AUTO_PROFILER_LABEL("PersistedOp::DoDirectoryWork", OTHER);
+
+  Nullable<bool> persisted = aQuotaManager.OriginPersisted(
+      OriginMetadata{mSuffix, mGroup, nsCString{mOriginScope.GetOrigin()},
+                     mPersistenceType.Value()});
+
+  if (!persisted.IsNull()) {
+    mPersisted = persisted.Value();
+    return NS_OK;
+  }
+
+  // If we get here, it means the origin hasn't been initialized yet.
+  // Try to get the persisted flag from directory metadata on disk.
+
+  QM_TRY_INSPECT(const auto& directory,
+                 aQuotaManager.GetDirectoryForOrigin(mPersistenceType.Value(),
+                                                     mOriginScope.GetOrigin()));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(directory, Exists));
+
+  if (exists) {
+    // Get the metadata. We only use the persisted flag.
+    QM_TRY_INSPECT(const auto& metadata,
+                   aQuotaManager.LoadFullOriginMetadataWithRestore(directory));
+
+    mPersisted = metadata.mPersisted;
+  } else {
+    // The directory has not been created yet.
+    mPersisted = false;
+  }
+
+  return NS_OK;
+}
+
+void PersistedOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  PersistedResponse persistedResponse;
+  persistedResponse.persisted() = mPersisted;
+
+  aResponse = persistedResponse;
+}
+
+PersistOp::PersistOp(const RequestParams& aParams)
+    : PersistRequestBase(aParams.get_PersistParams().principalInfo()) {
+  MOZ_ASSERT(aParams.type() == RequestParams::TPersistParams);
+}
+
+nsresult PersistOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+  MOZ_ASSERT(!mPersistenceType.IsNull());
+  MOZ_ASSERT(mPersistenceType.Value() == PERSISTENCE_TYPE_DEFAULT);
+  MOZ_ASSERT(mOriginScope.IsOrigin());
+
+  const OriginMetadata originMetadata = {mSuffix, mGroup,
+                                         nsCString{mOriginScope.GetOrigin()},
+                                         mPersistenceType.Value()};
+
+  AUTO_PROFILER_LABEL("PersistOp::DoDirectoryWork", OTHER);
+
+  // Update directory metadata on disk first. Then, create/update the originInfo
+  // if needed.
+  QM_TRY_INSPECT(const auto& directory,
+                 aQuotaManager.GetDirectoryForOrigin(mPersistenceType.Value(),
+                                                     originMetadata.mOrigin));
+
+  QM_TRY_INSPECT(const bool& created,
+                 aQuotaManager.EnsureOriginDirectory(*directory));
+
+  if (created) {
+    int64_t timestamp;
+
+    // Origin directory has been successfully created.
+    // Create OriginInfo too if temporary storage was already initialized.
+    if (aQuotaManager.IsTemporaryStorageInitialized()) {
+      timestamp = aQuotaManager.NoteOriginDirectoryCreated(
+          originMetadata, /* aPersisted */ true);
+    } else {
+      timestamp = PR_Now();
+    }
+
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(*directory, timestamp,
+                                                  /* aPersisted */ true,
+                                                  originMetadata)));
+  } else {
+    // Get the metadata (restore the metadata file if necessary). We only use
+    // the persisted flag.
+    QM_TRY_INSPECT(const auto& metadata,
+                   aQuotaManager.LoadFullOriginMetadataWithRestore(directory));
+
+    if (!metadata.mPersisted) {
+      QM_TRY_INSPECT(const auto& file,
+                     CloneFileAndAppend(
+                         *directory, nsLiteralString(METADATA_V2_FILE_NAME)));
+
+      QM_TRY_INSPECT(const auto& stream,
+                     GetBinaryOutputStream(*file, FileFlag::Update));
+
+      MOZ_ASSERT(stream);
+
+      // Update origin access time while we are here.
+      QM_TRY(MOZ_TO_RESULT(stream->Write64(PR_Now())));
+
+      // Set the persisted flag to true.
+      QM_TRY(MOZ_TO_RESULT(stream->WriteBoolean(true)));
+    }
+
+    // Directory metadata has been successfully updated.
+    // Update OriginInfo too if temporary storage was already initialized.
+    if (aQuotaManager.IsTemporaryStorageInitialized()) {
+      aQuotaManager.PersistOrigin(originMetadata);
+    }
+  }
+
+  return NS_OK;
+}
+
+void PersistOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = PersistResponse();
+}
+
+EstimateOp::EstimateOp(const EstimateParams& aParams)
+    : QuotaRequestBase("dom::quota::EstimateOp", /* aExclusive */ false),
+      mOriginMetadata(QuotaManager::GetInfoFromValidatedPrincipalInfo(
+                          aParams.principalInfo()),
+                      PERSISTENCE_TYPE_DEFAULT) {
+  AssertIsOnOwningThread();
+
+  // Overwrite OriginOperationBase default values.
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = true;
+}
+
+RefPtr<DirectoryLock> EstimateOp::CreateDirectoryLock() { return nullptr; }
+
+nsresult EstimateOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+
+  AUTO_PROFILER_LABEL("EstimateOp::DoDirectoryWork", OTHER);
+
+  // Ensure temporary storage is initialized. If temporary storage hasn't been
+  // initialized yet, the method will initialize it by traversing the
+  // repositories for temporary and default storage (including origins belonging
+  // to our group).
+  QM_TRY(MOZ_TO_RESULT(aQuotaManager.EnsureTemporaryStorageIsInitialized()));
+
+  // Get cached usage (the method doesn't have to stat any files).
+  mUsageAndLimit = aQuotaManager.GetUsageAndLimitForEstimate(mOriginMetadata);
+
+  return NS_OK;
+}
+
+void EstimateOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  EstimateResponse estimateResponse;
+
+  estimateResponse.usage() = mUsageAndLimit.first;
+  estimateResponse.limit() = mUsageAndLimit.second;
+
+  aResponse = estimateResponse;
+}
+
+ListOriginsOp::ListOriginsOp()
+    : QuotaRequestBase("dom::quota::ListOriginsOp", /* aExclusive */ false),
+      TraverseRepositoryHelper() {
+  AssertIsOnOwningThread();
+}
+
+void ListOriginsOp::Init(Quota& aQuota) {
+  AssertIsOnOwningThread();
+
+  mNeedsQuotaManagerInit = true;
+  mNeedsStorageInit = true;
+}
+
+nsresult ListOriginsOp::DoDirectoryWork(QuotaManager& aQuotaManager) {
+  AssertIsOnIOThread();
+  aQuotaManager.AssertStorageIsInitialized();
+
+  AUTO_PROFILER_LABEL("ListOriginsOp::DoDirectoryWork", OTHER);
+
+  for (const PersistenceType type : kAllPersistenceTypes) {
+    QM_TRY(MOZ_TO_RESULT(TraverseRepository(aQuotaManager, type)));
+  }
+
+  // TraverseRepository above only consulted the file-system to get a list of
+  // known origins, but we also need to include origins that have pending quota
+  // usage.
+
+  aQuotaManager.CollectPendingOriginsForListing([this](const auto& originInfo) {
+    mOrigins.AppendElement(originInfo->Origin());
+  });
+
+  return NS_OK;
+}
+
+const Atomic<bool>& ListOriginsOp::GetIsCanceledFlag() {
+  AssertIsOnIOThread();
+
+  return mCanceled;
+}
+
+nsresult ListOriginsOp::ProcessOrigin(QuotaManager& aQuotaManager,
+                                      nsIFile& aOriginDir,
+                                      const bool aPersistent,
+                                      const PersistenceType aPersistenceType) {
+  AssertIsOnIOThread();
+
+  // XXX We only use metadata.mOriginMetadata.mOrigin...
+  QM_TRY_UNWRAP(auto metadata,
+                aQuotaManager.LoadFullOriginMetadataWithRestore(&aOriginDir));
+
+  if (aQuotaManager.IsOriginInternal(metadata.mOrigin)) {
+    return NS_OK;
+  }
+
+  mOrigins.AppendElement(std::move(metadata.mOrigin));
+
+  return NS_OK;
+}
+
+void ListOriginsOp::GetResponse(RequestResponse& aResponse) {
+  AssertIsOnOwningThread();
+
+  aResponse = ListOriginsResponse();
+  if (mOrigins.IsEmpty()) {
+    return;
+  }
+
+  nsTArray<nsCString>& origins = aResponse.get_ListOriginsResponse().origins();
+  mOrigins.SwapElements(origins);
+}
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+
+// static
+already_AddRefed<PrincipalVerifier> PrincipalVerifier::CreateAndDispatch(
+    nsTArray<PrincipalInfo>&& aPrincipalInfos) {
+  AssertIsOnIOThread();
+
+  RefPtr<PrincipalVerifier> verifier =
+      new PrincipalVerifier(std::move(aPrincipalInfos));
+
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(verifier));
+
+  return verifier.forget();
+}
+
+Result<Ok, nsCString> PrincipalVerifier::CheckPrincipalInfoValidity(
+    const PrincipalInfo& aPrincipalInfo) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  switch (aPrincipalInfo.type()) {
+    // A system principal is acceptable.
+    case PrincipalInfo::TSystemPrincipalInfo: {
+      return Ok{};
+    }
+
+    case PrincipalInfo::TContentPrincipalInfo: {
+      const ContentPrincipalInfo& info =
+          aPrincipalInfo.get_ContentPrincipalInfo();
+
+      nsCOMPtr<nsIURI> uri;
+      nsresult rv = NS_NewURI(getter_AddRefs(uri), info.spec());
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return Err("NS_NewURI failed"_ns);
+      }
+
+      nsCOMPtr<nsIPrincipal> principal =
+          BasePrincipal::CreateContentPrincipal(uri, info.attrs());
+      if (NS_WARN_IF(!principal)) {
+        return Err("CreateContentPrincipal failed"_ns);
+      }
+
+      nsCString originNoSuffix;
+      rv = principal->GetOriginNoSuffix(originNoSuffix);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return Err("GetOriginNoSuffix failed"_ns);
+      }
+
+      if (NS_WARN_IF(originNoSuffix != info.originNoSuffix())) {
+        static const char messageTemplate[] =
+            "originNoSuffix (%s) doesn't match passed one (%s)!";
+
+        QM_WARNING(messageTemplate, originNoSuffix.get(),
+                   info.originNoSuffix().get());
+
+        return Err(nsPrintfCString(
+            messageTemplate, AnonymizedOriginString(originNoSuffix).get(),
+            AnonymizedOriginString(info.originNoSuffix()).get()));
+      }
+
+      nsCString baseDomain;
+      rv = principal->GetBaseDomain(baseDomain);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return Err("GetBaseDomain failed"_ns);
+      }
+
+      if (NS_WARN_IF(baseDomain != info.baseDomain())) {
+        static const char messageTemplate[] =
+            "baseDomain (%s) doesn't match passed one (%s)!";
+
+        QM_WARNING(messageTemplate, baseDomain.get(), info.baseDomain().get());
+
+        return Err(nsPrintfCString(messageTemplate,
+                                   AnonymizedCString(baseDomain).get(),
+                                   AnonymizedCString(info.baseDomain()).get()));
+      }
+
+      return Ok{};
+    }
+
+    default: {
+      break;
+    }
+  }
+
+  return Err("Null and expanded principals are not acceptable"_ns);
+}
+
+NS_IMETHODIMP
+PrincipalVerifier::Run() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsAutoCString allDetails;
+  for (auto& principalInfo : mPrincipalInfos) {
+    const auto res = CheckPrincipalInfoValidity(principalInfo);
+    if (res.isErr()) {
+      if (!allDetails.IsEmpty()) {
+        allDetails.AppendLiteral(", ");
+      }
+
+      allDetails.Append(res.inspectErr());
+    }
+  }
+
+  if (!allDetails.IsEmpty()) {
+    allDetails.Insert("Invalid principal infos found: ", 0);
+
+    // In case of invalid principal infos, this will produce a crash reason such
+    // as:
+    //   Invalid principal infos found: originNoSuffix (https://aaa.aaaaaaa.aaa)
+    //   doesn't match passed one (about:aaaa)!
+    //
+    // In case of errors while validating a principal, it will contain a
+    // different message describing that error, which does not contain any
+    // details of the actual principal info at the moment.
+    //
+    // This string will be leaked.
+    MOZ_CRASH_UNSAFE(strdup(allDetails.BeginReading()));
+  }
+
+  return NS_OK;
+}
+
+#endif
+
+nsresult StorageOperationBase::GetDirectoryMetadata(nsIFile* aDirectory,
+                                                    int64_t& aTimestamp,
+                                                    nsACString& aGroup,
+                                                    nsACString& aOrigin,
+                                                    Nullable<bool>& aIsApp) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aDirectory);
+
+  QM_TRY_INSPECT(
+      const auto& binaryStream,
+      GetBinaryInputStream(*aDirectory, nsLiteralString(METADATA_FILE_NAME)));
+
+  QM_TRY_INSPECT(const uint64_t& timestamp,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read64));
+
+  QM_TRY_INSPECT(const auto& group, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                        nsCString, binaryStream, ReadCString));
+
+  QM_TRY_INSPECT(const auto& origin, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                         nsCString, binaryStream, ReadCString));
+
+  Nullable<bool> isApp;
+  bool value;
+  if (NS_SUCCEEDED(binaryStream->ReadBoolean(&value))) {
+    isApp.SetValue(value);
+  }
+
+  aTimestamp = timestamp;
+  aGroup = group;
+  aOrigin = origin;
+  aIsApp = std::move(isApp);
+  return NS_OK;
+}
+
+nsresult StorageOperationBase::GetDirectoryMetadata2(
+    nsIFile* aDirectory, int64_t& aTimestamp, nsACString& aSuffix,
+    nsACString& aGroup, nsACString& aOrigin, bool& aIsApp) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aDirectory);
+
+  QM_TRY_INSPECT(const auto& binaryStream,
+                 GetBinaryInputStream(*aDirectory,
+                                      nsLiteralString(METADATA_V2_FILE_NAME)));
+
+  QM_TRY_INSPECT(const uint64_t& timestamp,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read64));
+
+  QM_TRY_INSPECT(const bool& persisted,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, ReadBoolean));
+  Unused << persisted;
+
+  QM_TRY_INSPECT(const bool& reservedData1,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read32));
+  Unused << reservedData1;
+
+  QM_TRY_INSPECT(const bool& reservedData2,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, Read32));
+  Unused << reservedData2;
+
+  QM_TRY_INSPECT(const auto& suffix, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                         nsCString, binaryStream, ReadCString));
+
+  QM_TRY_INSPECT(const auto& group, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                        nsCString, binaryStream, ReadCString));
+
+  QM_TRY_INSPECT(const auto& origin, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                         nsCString, binaryStream, ReadCString));
+
+  QM_TRY_INSPECT(const bool& isApp,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(binaryStream, ReadBoolean));
+
+  aTimestamp = timestamp;
+  aSuffix = suffix;
+  aGroup = group;
+  aOrigin = origin;
+  aIsApp = isApp;
+  return NS_OK;
+}
+
+int64_t StorageOperationBase::GetOriginLastModifiedTime(
+    const OriginProps& aOriginProps) {
+  return GetLastModifiedTime(*aOriginProps.mPersistenceType,
+                             *aOriginProps.mDirectory);
+}
+
+nsresult StorageOperationBase::RemoveObsoleteOrigin(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  QM_WARNING(
+      "Deleting obsolete %s directory that is no longer a legal "
+      "origin!",
+      NS_ConvertUTF16toUTF8(aOriginProps.mLeafName).get());
+
+  QM_TRY(MOZ_TO_RESULT(aOriginProps.mDirectory->Remove(/* recursive */ true)));
+
+  return NS_OK;
+}
+
+Result<bool, nsresult> StorageOperationBase::MaybeRenameOrigin(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  const nsAString& oldLeafName = aOriginProps.mLeafName;
+
+  const auto newLeafName =
+      MakeSanitizedOriginString(aOriginProps.mOriginMetadata.mOrigin);
+
+  if (oldLeafName == newLeafName) {
+    return false;
+  }
+
+  QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(*aOriginProps.mDirectory,
+                                               aOriginProps.mTimestamp,
+                                               aOriginProps.mOriginMetadata)));
+
+  QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+      *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+      /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+
+  QM_TRY_INSPECT(const auto& newFile,
+                 MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                     nsCOMPtr<nsIFile>, *aOriginProps.mDirectory, GetParent));
+
+  QM_TRY(MOZ_TO_RESULT(newFile->Append(newLeafName)));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(newFile, Exists));
+
+  if (exists) {
+    QM_WARNING(
+        "Can't rename %s directory to %s, the target already exists, removing "
+        "instead of renaming!",
+        NS_ConvertUTF16toUTF8(oldLeafName).get(),
+        NS_ConvertUTF16toUTF8(newLeafName).get());
+  }
+
+  QM_TRY(CallWithDelayedRetriesIfAccessDenied(
+      [&exists, &aOriginProps, &newLeafName] {
+        if (exists) {
+          QM_TRY_RETURN(MOZ_TO_RESULT(
+              aOriginProps.mDirectory->Remove(/* recursive */ true)));
+        }
+        QM_TRY_RETURN(MOZ_TO_RESULT(
+            aOriginProps.mDirectory->RenameTo(nullptr, newLeafName)));
+      },
+      StaticPrefs::dom_quotaManager_directoryRemovalOrRenaming_maxRetries(),
+      StaticPrefs::dom_quotaManager_directoryRemovalOrRenaming_delayMs()));
+
+  return true;
+}
+
+nsresult StorageOperationBase::ProcessOriginDirectories() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(!mOriginProps.IsEmpty());
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+  nsTArray<PrincipalInfo> principalInfos;
+#endif
+
+  for (auto& originProps : mOriginProps) {
+    switch (originProps.mType) {
+      case OriginProps::eChrome: {
+        originProps.mOriginMetadata = {QuotaManager::GetInfoForChrome(),
+                                       *originProps.mPersistenceType};
+        break;
+      }
+
+      case OriginProps::eContent: {
+        RefPtr<MozURL> specURL;
+        nsresult rv = MozURL::Init(getter_AddRefs(specURL), originProps.mSpec);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          // If a URL cannot be understood by MozURL during restoring or
+          // upgrading, either marking the directory as broken or removing that
+          // corresponding directory should be considered. While the cost of
+          // marking the directory as broken during a upgrade is too high,
+          // removing the directory is a better choice rather than blocking the
+          // initialization or the upgrade.
+          QM_WARNING(
+              "A URL (%s) for the origin directory is not recognized by "
+              "MozURL. The directory will be deleted for now to pass the "
+              "initialization or the upgrade.",
+              originProps.mSpec.get());
+
+          originProps.mType = OriginProps::eObsolete;
+          break;
+        }
+
+        nsCString originNoSuffix;
+        specURL->Origin(originNoSuffix);
+
+        QM_TRY_INSPECT(
+            const auto& baseDomain,
+            MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCString, specURL, BaseDomain));
+
+        ContentPrincipalInfo contentPrincipalInfo;
+        contentPrincipalInfo.attrs() = originProps.mAttrs;
+        contentPrincipalInfo.originNoSuffix() = originNoSuffix;
+        contentPrincipalInfo.spec() = originProps.mSpec;
+        contentPrincipalInfo.baseDomain() = baseDomain;
+
+        PrincipalInfo principalInfo(contentPrincipalInfo);
+
+        originProps.mOriginMetadata = {
+            QuotaManager::GetInfoFromValidatedPrincipalInfo(principalInfo),
+            *originProps.mPersistenceType};
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+        principalInfos.AppendElement(principalInfo);
+#endif
+
+        break;
+      }
+
+      case OriginProps::eObsolete: {
+        // There's no way to get info for obsolete origins.
+        break;
+      }
+
+      default:
+        MOZ_CRASH("Bad type!");
+    }
+  }
+
+#ifdef QM_PRINCIPALINFO_VERIFICATION_ENABLED
+  if (!principalInfos.IsEmpty()) {
+    RefPtr<PrincipalVerifier> principalVerifier =
+        PrincipalVerifier::CreateAndDispatch(std::move(principalInfos));
+  }
+#endif
+
+  // Don't try to upgrade obsolete origins, remove them right after we detect
+  // them.
+  for (const auto& originProps : mOriginProps) {
+    if (originProps.mType == OriginProps::eObsolete) {
+      MOZ_ASSERT(originProps.mOriginMetadata.mSuffix.IsEmpty());
+      MOZ_ASSERT(originProps.mOriginMetadata.mGroup.IsEmpty());
+      MOZ_ASSERT(originProps.mOriginMetadata.mOrigin.IsEmpty());
+
+      QM_TRY(MOZ_TO_RESULT(RemoveObsoleteOrigin(originProps)));
+    } else {
+      MOZ_ASSERT(!originProps.mOriginMetadata.mGroup.IsEmpty());
+      MOZ_ASSERT(!originProps.mOriginMetadata.mOrigin.IsEmpty());
+
+      QM_TRY(MOZ_TO_RESULT(ProcessOriginDirectory(originProps)));
+    }
+  }
+
+  return NS_OK;
+}
+
+// XXX Do the fallible initialization in a separate non-static member function
+// of StorageOperationBase and eventually get rid of this method and use a
+// normal constructor instead.
+template <typename PersistenceTypeFunc>
+nsresult StorageOperationBase::OriginProps::Init(
+    PersistenceTypeFunc&& aPersistenceTypeFunc) {
+  AssertIsOnIOThread();
+
+  QM_TRY_INSPECT(const auto& leafName,
+                 MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, *mDirectory,
+                                                   GetLeafName));
+
+  nsCString spec;
+  OriginAttributes attrs;
+  nsCString originalSuffix;
+  OriginParser::ResultType result = OriginParser::ParseOrigin(
+      NS_ConvertUTF16toUTF8(leafName), spec, &attrs, originalSuffix);
+  if (NS_WARN_IF(result == OriginParser::InvalidOrigin)) {
+    mType = OriginProps::eInvalid;
+    return NS_OK;
+  }
+
+  const auto persistenceType = [&]() -> PersistenceType {
+    // XXX We shouldn't continue with initialization if OriginParser returned
+    // anything else but ValidOrigin. Otherwise, we have to deal with empty
+    // spec when the origin is obsolete, like here. The caller should handle
+    // the errors. Until it's fixed, we have to treat obsolete origins as
+    // origins with unknown/invalid persistence type.
+    if (result != OriginParser::ValidOrigin) {
+      return PERSISTENCE_TYPE_INVALID;
+    }
+    return std::forward<PersistenceTypeFunc>(aPersistenceTypeFunc)(spec);
+  }();
+
+  mLeafName = leafName;
+  mSpec = spec;
+  mAttrs = attrs;
+  mOriginalSuffix = originalSuffix;
+  mPersistenceType.init(persistenceType);
+  if (result == OriginParser::ObsoleteOrigin) {
+    mType = eObsolete;
+  } else if (mSpec.EqualsLiteral(kChromeOrigin)) {
+    mType = eChrome;
+  } else {
+    mType = eContent;
+  }
+
+  return NS_OK;
+}
+
+// static
+auto OriginParser::ParseOrigin(const nsACString& aOrigin, nsCString& aSpec,
+                               OriginAttributes* aAttrs,
+                               nsCString& aOriginalSuffix) -> ResultType {
+  MOZ_ASSERT(!aOrigin.IsEmpty());
+  MOZ_ASSERT(aAttrs);
+
+  nsCString origin(aOrigin);
+  int32_t pos = origin.RFindChar('^');
+
+  if (pos == kNotFound) {
+    aOriginalSuffix.Truncate();
+  } else {
+    aOriginalSuffix = Substring(origin, pos);
+  }
+
+  OriginAttributes originAttributes;
+
+  nsCString originNoSuffix;
+  bool ok = originAttributes.PopulateFromOrigin(aOrigin, originNoSuffix);
+  if (!ok) {
+    return InvalidOrigin;
+  }
+
+  OriginParser parser(originNoSuffix);
+
+  *aAttrs = originAttributes;
+  return parser.Parse(aSpec);
+}
+
+auto OriginParser::Parse(nsACString& aSpec) -> ResultType {
+  while (mTokenizer.hasMoreTokens()) {
+    const nsDependentCSubstring& token = mTokenizer.nextToken();
+
+    HandleToken(token);
+
+    if (mError) {
+      break;
+    }
+
+    if (!mHandledTokens.IsEmpty()) {
+      mHandledTokens.AppendLiteral(", ");
+    }
+    mHandledTokens.Append('\'');
+    mHandledTokens.Append(token);
+    mHandledTokens.Append('\'');
+  }
+
+  if (!mError && mTokenizer.separatorAfterCurrentToken()) {
+    HandleTrailingSeparator();
+  }
+
+  if (mError) {
+    QM_WARNING("Origin '%s' failed to parse, handled tokens: %s", mOrigin.get(),
+               mHandledTokens.get());
+
+    return (mSchemeType == eChrome || mSchemeType == eAbout) ? ObsoleteOrigin
+                                                             : InvalidOrigin;
+  }
+
+  MOZ_ASSERT(mState == eComplete || mState == eHandledTrailingSeparator);
+
+  // For IPv6 URL, it should at least have three groups.
+  MOZ_ASSERT_IF(mIPGroup > 0, mIPGroup >= 3);
+
+  nsAutoCString spec(mScheme);
+
+  if (mSchemeType == eFile) {
+    spec.AppendLiteral("://");
+
+    if (mUniversalFileOrigin) {
+      MOZ_ASSERT(mPathnameComponents.Length() == 1);
+
+      spec.Append(mPathnameComponents[0]);
+    } else {
+      for (uint32_t count = mPathnameComponents.Length(), index = 0;
+           index < count; index++) {
+        spec.Append('/');
+        spec.Append(mPathnameComponents[index]);
+      }
+    }
+
+    aSpec = spec;
+
+    return ValidOrigin;
+  }
+
+  if (mSchemeType == eAbout) {
+    if (mMaybeObsolete) {
+      // The "moz-safe-about+++home" was acciedntally created by a buggy nightly
+      // and can be safely removed.
+      return mHost.EqualsLiteral("home") ? ObsoleteOrigin : InvalidOrigin;
+    }
+    spec.Append(':');
+  } else if (mSchemeType != eChrome) {
+    spec.AppendLiteral("://");
+  }
+
+  spec.Append(mHost);
+
+  if (!mPort.IsNull()) {
+    spec.Append(':');
+    spec.AppendInt(mPort.Value());
+  }
+
+  aSpec = spec;
+
+  return mScheme.EqualsLiteral("app") ? ObsoleteOrigin : ValidOrigin;
+}
+
+void OriginParser::HandleScheme(const nsDependentCSubstring& aToken) {
+  MOZ_ASSERT(!aToken.IsEmpty());
+  MOZ_ASSERT(mState == eExpectingAppIdOrScheme || mState == eExpectingScheme);
+
+  bool isAbout = false;
+  bool isMozSafeAbout = false;
+  bool isFile = false;
+  bool isChrome = false;
+  if (aToken.EqualsLiteral("http") || aToken.EqualsLiteral("https") ||
+      (isAbout = aToken.EqualsLiteral("about") ||
+                 (isMozSafeAbout = aToken.EqualsLiteral("moz-safe-about"))) ||
+      aToken.EqualsLiteral("indexeddb") ||
+      (isFile = aToken.EqualsLiteral("file")) || aToken.EqualsLiteral("app") ||
+      aToken.EqualsLiteral("resource") ||
+      aToken.EqualsLiteral("moz-extension") ||
+      (isChrome = aToken.EqualsLiteral(kChromeOrigin))) {
+    mScheme = aToken;
+
+    if (isAbout) {
+      mSchemeType = eAbout;
+      mState = isMozSafeAbout ? eExpectingEmptyToken1OrHost : eExpectingHost;
+    } else if (isChrome) {
+      mSchemeType = eChrome;
+      if (mTokenizer.hasMoreTokens()) {
+        mError = true;
+      }
+      mState = eComplete;
+    } else {
+      if (isFile) {
+        mSchemeType = eFile;
+      }
+      mState = eExpectingEmptyToken1;
+    }
+
+    return;
+  }
+
+  QM_WARNING("'%s' is not a valid scheme!", nsCString(aToken).get());
+
+  mError = true;
+}
+
+void OriginParser::HandlePathnameComponent(
+    const nsDependentCSubstring& aToken) {
+  MOZ_ASSERT(!aToken.IsEmpty());
+  MOZ_ASSERT(mState == eExpectingEmptyTokenOrDriveLetterOrPathnameComponent ||
+             mState == eExpectingEmptyTokenOrPathnameComponent);
+  MOZ_ASSERT(mSchemeType == eFile);
+
+  mPathnameComponents.AppendElement(aToken);
+
+  mState = mTokenizer.hasMoreTokens() ? eExpectingEmptyTokenOrPathnameComponent
+                                      : eComplete;
+}
+
+void OriginParser::HandleToken(const nsDependentCSubstring& aToken) {
+  switch (mState) {
+    case eExpectingAppIdOrScheme: {
+      if (aToken.IsEmpty()) {
+        QM_WARNING("Expected an app id or scheme (not an empty string)!");
+
+        mError = true;
+        return;
+      }
+
+      if (IsAsciiDigit(aToken.First())) {
+        // nsDependentCSubstring doesn't provice ToInteger()
+        nsCString token(aToken);
+
+        nsresult rv;
+        Unused << token.ToInteger(&rv);
+        if (NS_SUCCEEDED(rv)) {
+          mState = eExpectingInMozBrowser;
+          return;
+        }
+      }
+
+      HandleScheme(aToken);
+
+      return;
+    }
+
+    case eExpectingInMozBrowser: {
+      if (aToken.Length() != 1) {
+        QM_WARNING("'%zu' is not a valid length for the inMozBrowser flag!",
+                   aToken.Length());
+
+        mError = true;
+        return;
+      }
+
+      if (aToken.First() == 't') {
+        mInIsolatedMozBrowser = true;
+      } else if (aToken.First() == 'f') {
+        mInIsolatedMozBrowser = false;
+      } else {
+        QM_WARNING("'%s' is not a valid value for the inMozBrowser flag!",
+                   nsCString(aToken).get());
+
+        mError = true;
+        return;
+      }
+
+      mState = eExpectingScheme;
+
+      return;
+    }
+
+    case eExpectingScheme: {
+      if (aToken.IsEmpty()) {
+        QM_WARNING("Expected a scheme (not an empty string)!");
+
+        mError = true;
+        return;
+      }
+
+      HandleScheme(aToken);
+
+      return;
+    }
+
+    case eExpectingEmptyToken1: {
+      if (!aToken.IsEmpty()) {
+        QM_WARNING("Expected the first empty token!");
+
+        mError = true;
+        return;
+      }
+
+      mState = eExpectingEmptyToken2;
+
+      return;
+    }
+
+    case eExpectingEmptyToken2: {
+      if (!aToken.IsEmpty()) {
+        QM_WARNING("Expected the second empty token!");
+
+        mError = true;
+        return;
+      }
+
+      if (mSchemeType == eFile) {
+        mState = eExpectingEmptyTokenOrUniversalFileOrigin;
+      } else {
+        if (mSchemeType == eAbout) {
+          mMaybeObsolete = true;
+        }
+        mState = eExpectingHost;
+      }
+
+      return;
+    }
+
+    case eExpectingEmptyTokenOrUniversalFileOrigin: {
+      MOZ_ASSERT(mSchemeType == eFile);
+
+      if (aToken.IsEmpty()) {
+        mState = mTokenizer.hasMoreTokens()
+                     ? eExpectingEmptyTokenOrDriveLetterOrPathnameComponent
+                     : eComplete;
+
+        return;
+      }
+
+      if (aToken.EqualsLiteral("UNIVERSAL_FILE_URI_ORIGIN")) {
+        mUniversalFileOrigin = true;
+
+        mPathnameComponents.AppendElement(aToken);
+
+        mState = eComplete;
+
+        return;
+      }
+
+      QM_WARNING(
+          "Expected the third empty token or "
+          "UNIVERSAL_FILE_URI_ORIGIN!");
+
+      mError = true;
+      return;
+    }
+
+    case eExpectingHost: {
+      if (aToken.IsEmpty()) {
+        QM_WARNING("Expected a host (not an empty string)!");
+
+        mError = true;
+        return;
+      }
+
+      mHost = aToken;
+
+      if (aToken.First() == '[') {
+        MOZ_ASSERT(mIPGroup == 0);
+
+        ++mIPGroup;
+        mState = eExpectingIPV6Token;
+
+        MOZ_ASSERT(mTokenizer.hasMoreTokens());
+        return;
+      }
+
+      if (mTokenizer.hasMoreTokens()) {
+        if (mSchemeType == eAbout) {
+          QM_WARNING("Expected an empty string after host!");
+
+          mError = true;
+          return;
+        }
+
+        mState = eExpectingPort;
+
+        return;
+      }
+
+      mState = eComplete;
+
+      return;
+    }
+
+    case eExpectingPort: {
+      MOZ_ASSERT(mSchemeType == eNone);
+
+      if (aToken.IsEmpty()) {
+        QM_WARNING("Expected a port (not an empty string)!");
+
+        mError = true;
+        return;
+      }
+
+      // nsDependentCSubstring doesn't provice ToInteger()
+      nsCString token(aToken);
+
+      nsresult rv;
+      uint32_t port = token.ToInteger(&rv);
+      if (NS_SUCCEEDED(rv)) {
+        mPort.SetValue() = port;
+      } else {
+        QM_WARNING("'%s' is not a valid port number!", token.get());
+
+        mError = true;
+        return;
+      }
+
+      mState = eComplete;
+
+      return;
+    }
+
+    case eExpectingEmptyTokenOrDriveLetterOrPathnameComponent: {
+      MOZ_ASSERT(mSchemeType == eFile);
+
+      if (aToken.IsEmpty()) {
+        mPathnameComponents.AppendElement(""_ns);
+
+        mState = mTokenizer.hasMoreTokens()
+                     ? eExpectingEmptyTokenOrPathnameComponent
+                     : eComplete;
+
+        return;
+      }
+
+      if (aToken.Length() == 1 && IsAsciiAlpha(aToken.First())) {
+        mMaybeDriveLetter = true;
+
+        mPathnameComponents.AppendElement(aToken);
+
+        mState = mTokenizer.hasMoreTokens()
+                     ? eExpectingEmptyTokenOrPathnameComponent
+                     : eComplete;
+
+        return;
+      }
+
+      HandlePathnameComponent(aToken);
+
+      return;
+    }
+
+    case eExpectingEmptyTokenOrPathnameComponent: {
+      MOZ_ASSERT(mSchemeType == eFile);
+
+      if (aToken.IsEmpty()) {
+        if (mMaybeDriveLetter) {
+          MOZ_ASSERT(mPathnameComponents.Length() == 1);
+
+          nsCString& pathnameComponent = mPathnameComponents[0];
+          pathnameComponent.Append(':');
+
+          mMaybeDriveLetter = false;
+        } else {
+          mPathnameComponents.AppendElement(""_ns);
+        }
+
+        mState = mTokenizer.hasMoreTokens()
+                     ? eExpectingEmptyTokenOrPathnameComponent
+                     : eComplete;
+
+        return;
+      }
+
+      HandlePathnameComponent(aToken);
+
+      return;
+    }
+
+    case eExpectingEmptyToken1OrHost: {
+      MOZ_ASSERT(mSchemeType == eAbout &&
+                 mScheme.EqualsLiteral("moz-safe-about"));
+
+      if (aToken.IsEmpty()) {
+        mState = eExpectingEmptyToken2;
+      } else {
+        mHost = aToken;
+        mState = mTokenizer.hasMoreTokens() ? eExpectingPort : eComplete;
+      }
+
+      return;
+    }
+
+    case eExpectingIPV6Token: {
+      // A safe check for preventing infinity recursion.
+      if (++mIPGroup > 8) {
+        mError = true;
+        return;
+      }
+
+      mHost.AppendLiteral(":");
+      mHost.Append(aToken);
+      if (!aToken.IsEmpty() && aToken.Last() == ']') {
+        mState = mTokenizer.hasMoreTokens() ? eExpectingPort : eComplete;
+      }
+
+      return;
+    }
+
+    default:
+      MOZ_CRASH("Should never get here!");
+  }
+}
+
+void OriginParser::HandleTrailingSeparator() {
+  MOZ_ASSERT(mState == eComplete);
+  MOZ_ASSERT(mSchemeType == eFile);
+
+  mPathnameComponents.AppendElement(""_ns);
+
+  mState = eHandledTrailingSeparator;
+}
+
+nsresult RepositoryOperationBase::ProcessRepository() {
+  AssertIsOnIOThread();
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(mDirectory, Exists),
+                   QM_ASSERT_UNREACHABLE);
+    MOZ_ASSERT(exists);
+  }
+#endif
+
+  QM_TRY(CollectEachFileEntry(
+      *mDirectory,
+      [](const auto& originFile) -> Result<mozilla::Ok, nsresult> {
+        QM_TRY_INSPECT(const auto& leafName,
+                       MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                           nsAutoString, originFile, GetLeafName));
+
+        // Unknown files during upgrade are allowed. Just warn if we find
+        // them.
+        if (!IsOSMetadata(leafName)) {
+          UNKNOWN_FILE_WARNING(leafName);
+        }
+
+        return mozilla::Ok{};
+      },
+      [&self = *this](const auto& originDir) -> Result<mozilla::Ok, nsresult> {
+        OriginProps originProps(WrapMovingNotNullUnchecked(originDir));
+        QM_TRY(MOZ_TO_RESULT(originProps.Init([&self](const auto& aSpec) {
+          return self.PersistenceTypeFromSpec(aSpec);
+        })));
+        // Bypass invalid origins while upgrading
+        QM_TRY(OkIf(originProps.mType != OriginProps::eInvalid), mozilla::Ok{});
+
+        if (originProps.mType != OriginProps::eObsolete) {
+          QM_TRY_INSPECT(const bool& removed,
+                         MOZ_TO_RESULT_INVOKE_MEMBER(
+                             self, PrepareOriginDirectory, originProps));
+          if (removed) {
+            return mozilla::Ok{};
+          }
+        }
+
+        self.mOriginProps.AppendElement(std::move(originProps));
+
+        return mozilla::Ok{};
+      }));
+
+  if (mOriginProps.IsEmpty()) {
+    return NS_OK;
+  }
+
+  QM_TRY(MOZ_TO_RESULT(ProcessOriginDirectories()));
+
+  return NS_OK;
+}
+
+template <typename UpgradeMethod>
+nsresult RepositoryOperationBase::MaybeUpgradeClients(
+    const OriginProps& aOriginProps, UpgradeMethod aMethod) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aMethod);
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  QM_TRY(CollectEachFileEntry(
+      *aOriginProps.mDirectory,
+      [](const auto& file) -> Result<mozilla::Ok, nsresult> {
+        QM_TRY_INSPECT(
+            const auto& leafName,
+            MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, file, GetLeafName));
+
+        if (!IsOriginMetadata(leafName) && !IsTempMetadata(leafName)) {
+          UNKNOWN_FILE_WARNING(leafName);
+        }
+
+        return mozilla::Ok{};
+      },
+      [quotaManager, &aMethod,
+       &self = *this](const auto& dir) -> Result<mozilla::Ok, nsresult> {
+        QM_TRY_INSPECT(
+            const auto& leafName,
+            MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, dir, GetLeafName));
+
+        QM_TRY_INSPECT(const bool& removed,
+                       MOZ_TO_RESULT_INVOKE_MEMBER(self, PrepareClientDirectory,
+                                                   dir, leafName));
+        if (removed) {
+          return mozilla::Ok{};
+        }
+
+        Client::Type clientType;
+        bool ok = Client::TypeFromText(leafName, clientType, fallible);
+        if (!ok) {
+          UNKNOWN_FILE_WARNING(leafName);
+          return mozilla::Ok{};
+        }
+
+        Client* client = quotaManager->GetClient(clientType);
+        MOZ_ASSERT(client);
+
+        QM_TRY(MOZ_TO_RESULT((client->*aMethod)(dir)));
+
+        return mozilla::Ok{};
+      }));
+
+  return NS_OK;
+}
+
+nsresult RepositoryOperationBase::PrepareClientDirectory(
+    nsIFile* aFile, const nsAString& aLeafName, bool& aRemoved) {
+  AssertIsOnIOThread();
+
+  aRemoved = false;
+  return NS_OK;
+}
+
+nsresult CreateOrUpgradeDirectoryMetadataHelper::Init() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mDirectory);
+
+  const auto maybeLegacyPersistenceType =
+      LegacyPersistenceTypeFromFile(*mDirectory, fallible);
+  QM_TRY(OkIf(maybeLegacyPersistenceType.isSome()), Err(NS_ERROR_FAILURE));
+
+  mLegacyPersistenceType.init(maybeLegacyPersistenceType.value());
+
+  return NS_OK;
+}
+
+Maybe<CreateOrUpgradeDirectoryMetadataHelper::LegacyPersistenceType>
+CreateOrUpgradeDirectoryMetadataHelper::LegacyPersistenceTypeFromFile(
+    nsIFile& aFile, const fallible_t&) {
+  nsAutoString leafName;
+  MOZ_ALWAYS_SUCCEEDS(aFile.GetLeafName(leafName));
+
+  if (leafName.Equals(u"persistent"_ns)) {
+    return Some(LegacyPersistenceType::Persistent);
+  }
+
+  if (leafName.Equals(u"temporary"_ns)) {
+    return Some(LegacyPersistenceType::Temporary);
+  }
+
+  return Nothing();
+}
+
+PersistenceType
+CreateOrUpgradeDirectoryMetadataHelper::PersistenceTypeFromLegacyPersistentSpec(
+    const nsCString& aSpec) {
+  if (QuotaManager::IsOriginInternal(aSpec)) {
+    return PERSISTENCE_TYPE_PERSISTENT;
+  }
+
+  return PERSISTENCE_TYPE_DEFAULT;
+}
+
+PersistenceType CreateOrUpgradeDirectoryMetadataHelper::PersistenceTypeFromSpec(
+    const nsCString& aSpec) {
+  switch (*mLegacyPersistenceType) {
+    case LegacyPersistenceType::Persistent:
+      return PersistenceTypeFromLegacyPersistentSpec(aSpec);
+    case LegacyPersistenceType::Temporary:
+      return PERSISTENCE_TYPE_TEMPORARY;
+  }
+  MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Bad legacy persistence type value!");
+}
+
+nsresult CreateOrUpgradeDirectoryMetadataHelper::MaybeUpgradeOriginDirectory(
+    nsIFile* aDirectory) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aDirectory);
+
+  QM_TRY_INSPECT(
+      const auto& metadataFile,
+      CloneFileAndAppend(*aDirectory, nsLiteralString(METADATA_FILE_NAME)));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(metadataFile, Exists));
+
+  if (!exists) {
+    // Directory structure upgrade needed.
+    // Move all files to IDB specific directory.
+
+    nsString idbDirectoryName;
+    QM_TRY(OkIf(Client::TypeToText(Client::IDB, idbDirectoryName, fallible)),
+           NS_ERROR_FAILURE);
+
+    QM_TRY_INSPECT(const auto& idbDirectory,
+                   CloneFileAndAppend(*aDirectory, idbDirectoryName));
+
+    // Usually we only use QM_OR_ELSE_LOG_VERBOSE/QM_OR_ELSE_LOG_VERBOSE_IF
+    // with Create and NS_ERROR_FILE_ALREADY_EXISTS check, but typically the
+    // idb directory shouldn't exist during the upgrade and the upgrade runs
+    // only once in most of the cases, so the use of QM_OR_ELSE_WARN_IF is ok
+    // here.
+    QM_TRY(QM_OR_ELSE_WARN_IF(
+        // Expression.
+        MOZ_TO_RESULT(idbDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755)),
+        // Predicate.
+        IsSpecificError<NS_ERROR_FILE_ALREADY_EXISTS>,
+        // Fallback.
+        ([&idbDirectory](const nsresult rv) -> Result<Ok, nsresult> {
+          QM_TRY_INSPECT(
+              const bool& isDirectory,
+              MOZ_TO_RESULT_INVOKE_MEMBER(idbDirectory, IsDirectory));
+
+          QM_TRY(OkIf(isDirectory), Err(NS_ERROR_UNEXPECTED));
+
+          return Ok{};
+        })));
+
+    QM_TRY(CollectEachFile(
+        *aDirectory,
+        [&idbDirectory, &idbDirectoryName](
+            const nsCOMPtr<nsIFile>& file) -> Result<Ok, nsresult> {
+          QM_TRY_INSPECT(const auto& leafName,
+                         MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsAutoString, file,
+                                                           GetLeafName));
+
+          if (!leafName.Equals(idbDirectoryName)) {
+            QM_TRY(MOZ_TO_RESULT(file->MoveTo(idbDirectory, u""_ns)));
+          }
+
+          return Ok{};
+        }));
+
+    QM_TRY(
+        MOZ_TO_RESULT(metadataFile->Create(nsIFile::NORMAL_FILE_TYPE, 0644)));
+  }
+
+  return NS_OK;
+}
+
+nsresult CreateOrUpgradeDirectoryMetadataHelper::PrepareOriginDirectory(
+    OriginProps& aOriginProps, bool* aRemoved) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aRemoved);
+
+  if (*mLegacyPersistenceType == LegacyPersistenceType::Persistent) {
+    QM_TRY(MOZ_TO_RESULT(
+        MaybeUpgradeOriginDirectory(aOriginProps.mDirectory.get())));
+
+    aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+  } else {
+    int64_t timestamp;
+    nsCString group;
+    nsCString origin;
+    Nullable<bool> isApp;
+
+    QM_WARNONLY_TRY_UNWRAP(
+        const auto maybeDirectoryMetadata,
+        MOZ_TO_RESULT(GetDirectoryMetadata(aOriginProps.mDirectory.get(),
+                                           timestamp, group, origin, isApp)));
+    if (!maybeDirectoryMetadata) {
+      aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+      aOriginProps.mNeedsRestore = true;
+    } else if (!isApp.IsNull()) {
+      aOriginProps.mIgnore = true;
+    }
+  }
+
+  *aRemoved = false;
+  return NS_OK;
+}
+
+nsresult CreateOrUpgradeDirectoryMetadataHelper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  if (*mLegacyPersistenceType == LegacyPersistenceType::Persistent) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+
+    // Move internal origins to new persistent storage.
+    if (PersistenceTypeFromLegacyPersistentSpec(aOriginProps.mSpec) ==
+        PERSISTENCE_TYPE_PERSISTENT) {
+      if (!mPermanentStorageDir) {
+        QuotaManager* quotaManager = QuotaManager::Get();
+        MOZ_ASSERT(quotaManager);
+
+        const nsString& permanentStoragePath =
+            quotaManager->GetStoragePath(PERSISTENCE_TYPE_PERSISTENT);
+
+        QM_TRY_UNWRAP(mPermanentStorageDir,
+                      QM_NewLocalFile(permanentStoragePath));
+      }
+
+      const nsAString& leafName = aOriginProps.mLeafName;
+
+      QM_TRY_INSPECT(const auto& newDirectory,
+                     CloneFileAndAppend(*mPermanentStorageDir, leafName));
+
+      QM_TRY_INSPECT(const bool& exists,
+                     MOZ_TO_RESULT_INVOKE_MEMBER(newDirectory, Exists));
+
+      if (exists) {
+        QM_WARNING("Found %s in storage/persistent and storage/permanent !",
+                   NS_ConvertUTF16toUTF8(leafName).get());
+
+        QM_TRY(MOZ_TO_RESULT(
+            aOriginProps.mDirectory->Remove(/* recursive */ true)));
+      } else {
+        QM_TRY(MOZ_TO_RESULT(
+            aOriginProps.mDirectory->MoveTo(mPermanentStorageDir, u""_ns)));
+      }
+    }
+  } else if (aOriginProps.mNeedsRestore) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+  } else if (!aOriginProps.mIgnore) {
+    QM_TRY_INSPECT(const auto& file,
+                   CloneFileAndAppend(*aOriginProps.mDirectory,
+                                      nsLiteralString(METADATA_FILE_NAME)));
+
+    QM_TRY_INSPECT(const auto& stream,
+                   GetBinaryOutputStream(*file, FileFlag::Append));
+
+    MOZ_ASSERT(stream);
+
+    // Currently unused (used to be isApp).
+    QM_TRY(MOZ_TO_RESULT(stream->WriteBoolean(false)));
+  }
+
+  return NS_OK;
+}
+
+nsresult UpgradeStorageHelperBase::Init() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mDirectory);
+
+  const auto maybePersistenceType =
+      PersistenceTypeFromFile(*mDirectory, fallible);
+  QM_TRY(OkIf(maybePersistenceType.isSome()), Err(NS_ERROR_FAILURE));
+
+  mPersistenceType.init(maybePersistenceType.value());
+
+  return NS_OK;
+}
+
+PersistenceType UpgradeStorageHelperBase::PersistenceTypeFromSpec(
+    const nsCString& aSpec) {
+  // There's no moving of origin directories between repositories like in the
+  // CreateOrUpgradeDirectoryMetadataHelper
+  return *mPersistenceType;
+}
+
+nsresult UpgradeStorageFrom0_0To1_0Helper::PrepareOriginDirectory(
+    OriginProps& aOriginProps, bool* aRemoved) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aRemoved);
+
+  int64_t timestamp;
+  nsCString group;
+  nsCString origin;
+  Nullable<bool> isApp;
+
+  QM_WARNONLY_TRY_UNWRAP(
+      const auto maybeDirectoryMetadata,
+      MOZ_TO_RESULT(GetDirectoryMetadata(aOriginProps.mDirectory.get(),
+                                         timestamp, group, origin, isApp)));
+  if (!maybeDirectoryMetadata || isApp.IsNull()) {
+    aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+    aOriginProps.mNeedsRestore = true;
+  } else {
+    aOriginProps.mTimestamp = timestamp;
+  }
+
+  *aRemoved = false;
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom0_0To1_0Helper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  // This handles changes in origin string generation from nsIPrincipal,
+  // especially the change from: appId+inMozBrowser+originNoSuffix
+  // to: origin (with origin suffix).
+  QM_TRY_INSPECT(const bool& renamed, MaybeRenameOrigin(aOriginProps));
+  if (renamed) {
+    return NS_OK;
+  }
+
+  if (aOriginProps.mNeedsRestore) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+  }
+
+  QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+      *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+      /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom1_0To2_0Helper::MaybeRemoveMorgueDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  // The Cache API was creating top level morgue directories by accident for
+  // a short time in nightly.  This unfortunately prevents all storage from
+  // working.  So recover these profiles permanently by removing these corrupt
+  // directories as part of this upgrade.
+
+  QM_TRY_INSPECT(const auto& morgueDir,
+                 MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                     nsCOMPtr<nsIFile>, *aOriginProps.mDirectory, Clone));
+
+  QM_TRY(MOZ_TO_RESULT(morgueDir->Append(u"morgue"_ns)));
+
+  QM_TRY_INSPECT(const bool& exists,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(morgueDir, Exists));
+
+  if (exists) {
+    QM_WARNING("Deleting accidental morgue directory!");
+
+    QM_TRY(MOZ_TO_RESULT(morgueDir->Remove(/* recursive */ true)));
+  }
+
+  return NS_OK;
+}
+
+Result<bool, nsresult> UpgradeStorageFrom1_0To2_0Helper::MaybeRemoveAppsData(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  // TODO: This method was empty for some time due to accidental changes done
+  //       in bug 1320404. This led to renaming of origin directories like:
+  //         https+++developer.cdn.mozilla.net^appId=1007&inBrowser=1
+  //       to:
+  //         https+++developer.cdn.mozilla.net^inBrowser=1
+  //       instead of just removing them.
+
+  const nsCString& originalSuffix = aOriginProps.mOriginalSuffix;
+  if (!originalSuffix.IsEmpty()) {
+    MOZ_ASSERT(originalSuffix[0] == '^');
+
+    if (!URLParams::Parse(
+            Substring(originalSuffix, 1, originalSuffix.Length() - 1),
+            [](const nsAString& aName, const nsAString& aValue) {
+              if (aName.EqualsLiteral("appId")) {
+                return false;
+              }
+
+              return true;
+            })) {
+      QM_TRY(MOZ_TO_RESULT(RemoveObsoleteOrigin(aOriginProps)));
+
+      return true;
+    }
+  }
+
+  return false;
+}
+
+nsresult UpgradeStorageFrom1_0To2_0Helper::PrepareOriginDirectory(
+    OriginProps& aOriginProps, bool* aRemoved) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aRemoved);
+
+  QM_TRY(MOZ_TO_RESULT(MaybeRemoveMorgueDirectory(aOriginProps)));
+
+  QM_TRY(MOZ_TO_RESULT(
+      MaybeUpgradeClients(aOriginProps, &Client::UpgradeStorageFrom1_0To2_0)));
+
+  QM_TRY_INSPECT(const bool& removed, MaybeRemoveAppsData(aOriginProps));
+  if (removed) {
+    *aRemoved = true;
+    return NS_OK;
+  }
+
+  int64_t timestamp;
+  nsCString group;
+  nsCString origin;
+  Nullable<bool> isApp;
+  QM_WARNONLY_TRY_UNWRAP(
+      const auto maybeDirectoryMetadata,
+      MOZ_TO_RESULT(GetDirectoryMetadata(aOriginProps.mDirectory.get(),
+                                         timestamp, group, origin, isApp)));
+  if (!maybeDirectoryMetadata || isApp.IsNull()) {
+    aOriginProps.mNeedsRestore = true;
+  }
+
+  nsCString suffix;
+  QM_WARNONLY_TRY_UNWRAP(const auto maybeDirectoryMetadata2,
+                         MOZ_TO_RESULT(GetDirectoryMetadata2(
+                             aOriginProps.mDirectory.get(), timestamp, suffix,
+                             group, origin, isApp.SetValue())));
+  if (!maybeDirectoryMetadata2) {
+    aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+    aOriginProps.mNeedsRestore2 = true;
+  } else {
+    aOriginProps.mTimestamp = timestamp;
+  }
+
+  *aRemoved = false;
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom1_0To2_0Helper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  // This handles changes in origin string generation from nsIPrincipal,
+  // especially the stripping of obsolete origin attributes like addonId.
+  QM_TRY_INSPECT(const bool& renamed, MaybeRenameOrigin(aOriginProps));
+  if (renamed) {
+    return NS_OK;
+  }
+
+  if (aOriginProps.mNeedsRestore) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+  }
+
+  if (aOriginProps.mNeedsRestore2) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+  }
+
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom2_0To2_1Helper::PrepareOriginDirectory(
+    OriginProps& aOriginProps, bool* aRemoved) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aRemoved);
+
+  QM_TRY(MOZ_TO_RESULT(
+      MaybeUpgradeClients(aOriginProps, &Client::UpgradeStorageFrom2_0To2_1)));
+
+  int64_t timestamp;
+  nsCString group;
+  nsCString origin;
+  Nullable<bool> isApp;
+  QM_WARNONLY_TRY_UNWRAP(
+      const auto maybeDirectoryMetadata,
+      MOZ_TO_RESULT(GetDirectoryMetadata(aOriginProps.mDirectory.get(),
+                                         timestamp, group, origin, isApp)));
+  if (!maybeDirectoryMetadata || isApp.IsNull()) {
+    aOriginProps.mNeedsRestore = true;
+  }
+
+  nsCString suffix;
+  QM_WARNONLY_TRY_UNWRAP(const auto maybeDirectoryMetadata2,
+                         MOZ_TO_RESULT(GetDirectoryMetadata2(
+                             aOriginProps.mDirectory.get(), timestamp, suffix,
+                             group, origin, isApp.SetValue())));
+  if (!maybeDirectoryMetadata2) {
+    aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+    aOriginProps.mNeedsRestore2 = true;
+  } else {
+    aOriginProps.mTimestamp = timestamp;
+  }
+
+  *aRemoved = false;
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom2_0To2_1Helper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  if (aOriginProps.mNeedsRestore) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+  }
+
+  if (aOriginProps.mNeedsRestore2) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+  }
+
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom2_1To2_2Helper::PrepareOriginDirectory(
+    OriginProps& aOriginProps, bool* aRemoved) {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(aRemoved);
+
+  QM_TRY(MOZ_TO_RESULT(
+      MaybeUpgradeClients(aOriginProps, &Client::UpgradeStorageFrom2_1To2_2)));
+
+  int64_t timestamp;
+  nsCString group;
+  nsCString origin;
+  Nullable<bool> isApp;
+  QM_WARNONLY_TRY_UNWRAP(
+      const auto maybeDirectoryMetadata,
+      MOZ_TO_RESULT(GetDirectoryMetadata(aOriginProps.mDirectory.get(),
+                                         timestamp, group, origin, isApp)));
+  if (!maybeDirectoryMetadata || isApp.IsNull()) {
+    aOriginProps.mNeedsRestore = true;
+  }
+
+  nsCString suffix;
+  QM_WARNONLY_TRY_UNWRAP(const auto maybeDirectoryMetadata2,
+                         MOZ_TO_RESULT(GetDirectoryMetadata2(
+                             aOriginProps.mDirectory.get(), timestamp, suffix,
+                             group, origin, isApp.SetValue())));
+  if (!maybeDirectoryMetadata2) {
+    aOriginProps.mTimestamp = GetOriginLastModifiedTime(aOriginProps);
+    aOriginProps.mNeedsRestore2 = true;
+  } else {
+    aOriginProps.mTimestamp = timestamp;
+  }
+
+  *aRemoved = false;
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom2_1To2_2Helper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  if (aOriginProps.mNeedsRestore) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        aOriginProps.mOriginMetadata)));
+  }
+
+  if (aOriginProps.mNeedsRestore2) {
+    QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+        *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+        /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+  }
+
+  return NS_OK;
+}
+
+nsresult UpgradeStorageFrom2_1To2_2Helper::PrepareClientDirectory(
+    nsIFile* aFile, const nsAString& aLeafName, bool& aRemoved) {
+  AssertIsOnIOThread();
+
+  if (Client::IsDeprecatedClient(aLeafName)) {
+    QM_WARNING("Deleting deprecated %s client!",
+               NS_ConvertUTF16toUTF8(aLeafName).get());
+
+    QM_TRY(MOZ_TO_RESULT(aFile->Remove(true)));
+
+    aRemoved = true;
+  } else {
+    aRemoved = false;
+  }
+
+  return NS_OK;
+}
+
+nsresult RestoreDirectoryMetadata2Helper::Init() {
+  AssertIsOnIOThread();
+  MOZ_ASSERT(mDirectory);
+
+  nsCOMPtr<nsIFile> parentDir;
+  QM_TRY(MOZ_TO_RESULT(mDirectory->GetParent(getter_AddRefs(parentDir))));
+
+  const auto maybePersistenceType =
+      PersistenceTypeFromFile(*parentDir, fallible);
+  QM_TRY(OkIf(maybePersistenceType.isSome()), Err(NS_ERROR_FAILURE));
+
+  mPersistenceType.init(maybePersistenceType.value());
+
+  return NS_OK;
+}
+
+nsresult RestoreDirectoryMetadata2Helper::RestoreMetadata2File() {
+  OriginProps originProps(WrapMovingNotNull(mDirectory));
+  QM_TRY(MOZ_TO_RESULT(originProps.Init(
+      [&self = *this](const auto& aSpec) { return *self.mPersistenceType; })));
+
+  QM_TRY(OkIf(originProps.mType != OriginProps::eInvalid), NS_ERROR_FAILURE);
+
+  originProps.mTimestamp = GetOriginLastModifiedTime(originProps);
+
+  mOriginProps.AppendElement(std::move(originProps));
+
+  QM_TRY(MOZ_TO_RESULT(ProcessOriginDirectories()));
+
+  return NS_OK;
+}
+
+nsresult RestoreDirectoryMetadata2Helper::ProcessOriginDirectory(
+    const OriginProps& aOriginProps) {
+  AssertIsOnIOThread();
+
+  // We don't have any approach to restore aPersisted, so reset it to false.
+  QM_TRY(MOZ_TO_RESULT(CreateDirectoryMetadata2(
+      *aOriginProps.mDirectory, aOriginProps.mTimestamp,
+      /* aPersisted */ false, aOriginProps.mOriginMetadata)));
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/ActorsParent.h b/dom/quota/ActorsParent.h
new file mode 100644
index 0000000000..4f8fcebd3e
--- /dev/null
+++ b/dom/quota/ActorsParent.h
@@ -0,0 +1,26 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_ActorsParent_h
+#define mozilla_dom_quota_ActorsParent_h
+
+#include "mozilla/dom/quota/Config.h"
+
+namespace mozilla::dom::quota {
+
+class PQuotaParent;
+
+void InitializeQuotaManager();
+
+PQuotaParent* AllocPQuotaParent();
+
+bool DeallocPQuotaParent(PQuotaParent* aActor);
+
+bool RecvShutdownQuotaManager();
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_ActorsParent_h
diff --git a/dom/quota/Assertions.cpp b/dom/quota/Assertions.cpp
new file mode 100644
index 0000000000..a2dd155743
--- /dev/null
+++ b/dom/quota/Assertions.cpp
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Assertions.h"
+
+namespace mozilla::dom::quota {
+
+bool IsOnIOThread() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  NS_ASSERTION(quotaManager, "Must have a manager here!");
+
+  bool currentThread;
+  return NS_SUCCEEDED(
+             quotaManager->IOThread()->IsOnCurrentThread(&currentThread)) &&
+         currentThread;
+}
+
+void AssertIsOnIOThread() {
+  NS_ASSERTION(IsOnIOThread(), "Running on the wrong thread!");
+}
+
+void DiagnosticAssertIsOnIOThread() { MOZ_DIAGNOSTIC_ASSERT(IsOnIOThread()); }
+
+void AssertCurrentThreadOwnsQuotaMutex() {
+#ifdef DEBUG
+  QuotaManager* quotaManager = QuotaManager::Get();
+  NS_ASSERTION(quotaManager, "Must have a manager here!");
+
+  quotaManager->AssertCurrentThreadOwnsQuotaMutex();
+#endif
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/Assertions.h b/dom/quota/Assertions.h
new file mode 100644
index 0000000000..d2eacb0c1d
--- /dev/null
+++ b/dom/quota/Assertions.h
@@ -0,0 +1,30 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_ASSERTIONS_H_
+#define DOM_QUOTA_ASSERTIONS_H_
+
+#include <cstdint>
+
+namespace mozilla::dom::quota {
+
+template <typename T>
+void AssertNoOverflow(uint64_t aDest, T aArg);
+
+template <typename T, typename U>
+void AssertNoUnderflow(T aDest, U aArg);
+
+bool IsOnIOThread();
+
+void AssertIsOnIOThread();
+
+void DiagnosticAssertIsOnIOThread();
+
+void AssertCurrentThreadOwnsQuotaMutex();
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_ASSERTIONS_H_
diff --git a/dom/quota/AssertionsImpl.h b/dom/quota/AssertionsImpl.h
new file mode 100644
index 0000000000..77df103311
--- /dev/null
+++ b/dom/quota/AssertionsImpl.h
@@ -0,0 +1,52 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_ASSERTIONSIMPL_H_
+#define DOM_QUOTA_ASSERTIONSIMPL_H_
+
+#include "mozilla/dom/quota/Assertions.h"
+
+#include <type_traits>
+#include "mozilla/Assertions.h"
+
+namespace mozilla::dom::quota {
+
+namespace detail {
+
+template <typename T, bool = std::is_unsigned_v<T>>
+struct IntChecker {
+  static void Assert(T aInt) {
+    static_assert(std::is_integral_v<T>, "Not an integer!");
+    MOZ_ASSERT(aInt >= 0);
+  }
+};
+
+template <typename T>
+struct IntChecker<T, true> {
+  static void Assert(T aInt) {
+    static_assert(std::is_integral_v<T>, "Not an integer!");
+  }
+};
+
+}  // namespace detail
+
+template <typename T>
+void AssertNoOverflow(uint64_t aDest, T aArg) {
+  detail::IntChecker<T>::Assert(aDest);
+  detail::IntChecker<T>::Assert(aArg);
+  MOZ_ASSERT(UINT64_MAX - aDest >= uint64_t(aArg));
+}
+
+template <typename T, typename U>
+void AssertNoUnderflow(T aDest, U aArg) {
+  detail::IntChecker<T>::Assert(aDest);
+  detail::IntChecker<T>::Assert(aArg);
+  MOZ_ASSERT(uint64_t(aDest) >= uint64_t(aArg));
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_ASSERTIONSIMPL_H_
diff --git a/dom/quota/CachingDatabaseConnection.cpp b/dom/quota/CachingDatabaseConnection.cpp
new file mode 100644
index 0000000000..cd07dba4e7
--- /dev/null
+++ b/dom/quota/CachingDatabaseConnection.cpp
@@ -0,0 +1,193 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/CachingDatabaseConnection.h"
+
+#include "mozilla/ProfilerLabels.h"
+#include "mozilla/ipc/BackgroundParent.h"
+
+namespace mozilla::dom::quota {
+
+CachingDatabaseConnection::CachingDatabaseConnection(
+    MovingNotNull<nsCOMPtr<mozIStorageConnection>> aStorageConnection)
+    :
+#ifdef MOZ_THREAD_SAFETY_OWNERSHIP_CHECKS_SUPPORTED
+      mOwningThread{nsAutoOwningThread{}},
+#endif
+      mStorageConnection(std::move(aStorageConnection)) {
+}
+
+void CachingDatabaseConnection::LazyInit(
+    MovingNotNull<nsCOMPtr<mozIStorageConnection>> aStorageConnection) {
+#ifdef MOZ_THREAD_SAFETY_OWNERSHIP_CHECKS_SUPPORTED
+  mOwningThread.init();
+#endif
+  mStorageConnection.init(std::move(aStorageConnection));
+}
+
+Result<CachingDatabaseConnection::CachedStatement, nsresult>
+CachingDatabaseConnection::GetCachedStatement(const nsACString& aQuery) {
+  AssertIsOnConnectionThread();
+  MOZ_ASSERT(!aQuery.IsEmpty());
+  MOZ_ASSERT(mStorageConnection);
+
+  AUTO_PROFILER_LABEL("CachingDatabaseConnection::GetCachedStatement", DOM);
+
+  QM_TRY_UNWRAP(
+      auto stmt,
+      mCachedStatements.TryLookupOrInsertWith(
+          aQuery, [&]() -> Result<nsCOMPtr<mozIStorageStatement>, nsresult> {
+            const auto extraInfo =
+                ScopedLogExtraInfo{ScopedLogExtraInfo::kTagQuery, aQuery};
+
+            QM_TRY_RETURN(
+                MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                    nsCOMPtr<mozIStorageStatement>, **mStorageConnection,
+                    CreateStatement, aQuery),
+                QM_PROPAGATE,
+                ([&aQuery,
+                  &storageConnection = **mStorageConnection](const auto&) {
+#ifdef DEBUG
+                  nsCString msg;
+                  MOZ_ALWAYS_SUCCEEDS(
+                      storageConnection.GetLastErrorString(msg));
+
+                  nsAutoCString error =
+                      "The statement '"_ns + aQuery +
+                      "' failed to compile with the error message '"_ns + msg +
+                      "'."_ns;
+
+                  NS_WARNING(error.get());
+#else
+                    (void)aQuery;
+#endif
+                }));
+          }));
+
+  return CachedStatement{this, std::move(stmt), aQuery};
+}
+
+Result<CachingDatabaseConnection::BorrowedStatement, nsresult>
+CachingDatabaseConnection::BorrowCachedStatement(const nsACString& aQuery) {
+  QM_TRY_UNWRAP(auto cachedStatement, GetCachedStatement(aQuery));
+
+  return cachedStatement.Borrow();
+}
+
+nsresult CachingDatabaseConnection::ExecuteCachedStatement(
+    const nsACString& aQuery) {
+  return ExecuteCachedStatement(
+      aQuery, [](auto&) -> Result<Ok, nsresult> { return Ok{}; });
+}
+
+void CachingDatabaseConnection::Close() {
+  AssertIsOnConnectionThread();
+  MOZ_ASSERT(HasStorageConnection());
+
+  AUTO_PROFILER_LABEL("CachingDatabaseConnection::Close", DOM);
+
+  mCachedStatements.Clear();
+
+  MOZ_ALWAYS_SUCCEEDS((*mStorageConnection)->Close());
+  mStorageConnection.destroy();
+}
+
+#if defined(DEBUG) || defined(NS_BUILD_REFCNT_LOGGING)
+CachingDatabaseConnection::CachedStatement::CachedStatement()
+#  ifdef DEBUG
+    : mDEBUGConnection(nullptr)
+#  endif
+{
+  AssertIsOnConnectionThread();
+
+  MOZ_COUNT_CTOR(CachingDatabaseConnection::CachedStatement);
+}
+
+CachingDatabaseConnection::CachedStatement::~CachedStatement() {
+  AssertIsOnConnectionThread();
+
+  MOZ_COUNT_DTOR(CachingDatabaseConnection::CachedStatement);
+}
+#endif
+
+CachingDatabaseConnection::CachedStatement::operator bool() const {
+  AssertIsOnConnectionThread();
+
+  return mStatement;
+}
+
+mozIStorageStatement& CachingDatabaseConnection::BorrowedStatement::operator*()
+    const {
+  return *operator->();
+}
+
+mozIStorageStatement* CachingDatabaseConnection::BorrowedStatement::operator->()
+    const {
+  MOZ_ASSERT(mStatement);
+
+  return mStatement;
+}
+
+CachingDatabaseConnection::BorrowedStatement
+CachingDatabaseConnection::CachedStatement::Borrow() const {
+  AssertIsOnConnectionThread();
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  return BorrowedStatement{WrapNotNull(mStatement), mQuery};
+#else
+  return BorrowedStatement{WrapNotNull(mStatement)};
+#endif
+}
+
+CachingDatabaseConnection::CachedStatement::CachedStatement(
+    CachingDatabaseConnection* aConnection,
+    nsCOMPtr<mozIStorageStatement> aStatement, const nsACString& aQuery)
+    : mStatement(std::move(aStatement))
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+      ,
+      mQuery(aQuery)
+#endif
+#if defined(DEBUG)
+      ,
+      mDEBUGConnection(aConnection)
+#endif
+{
+#ifdef DEBUG
+  MOZ_ASSERT(aConnection);
+  aConnection->AssertIsOnConnectionThread();
+#endif
+  MOZ_ASSERT(mStatement);
+  AssertIsOnConnectionThread();
+
+  MOZ_COUNT_CTOR(CachingDatabaseConnection::CachedStatement);
+}
+
+void CachingDatabaseConnection::CachedStatement::AssertIsOnConnectionThread()
+    const {
+#ifdef DEBUG
+  if (mDEBUGConnection) {
+    mDEBUGConnection->AssertIsOnConnectionThread();
+  }
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(!mozilla::ipc::IsOnBackgroundThread());
+#endif
+}
+
+Result<CachingDatabaseConnection::BorrowedStatement, nsresult>
+CachingDatabaseConnection::LazyStatement::Borrow() {
+  if (!mCachedStatement) {
+    QM_TRY(Initialize());
+  }
+
+  return mCachedStatement.Borrow();
+}
+
+Result<Ok, nsresult> CachingDatabaseConnection::LazyStatement::Initialize() {
+  QM_TRY_UNWRAP(mCachedStatement, mConnection.GetCachedStatement(mQueryString));
+  return Ok{};
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/CachingDatabaseConnection.h b/dom/quota/CachingDatabaseConnection.h
new file mode 100644
index 0000000000..355baf5293
--- /dev/null
+++ b/dom/quota/CachingDatabaseConnection.h
@@ -0,0 +1,238 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_CACHINGDATABASECONNECTION_H_
+#define DOM_QUOTA_CACHINGDATABASECONNECTION_H_
+
+#include "mozilla/dom/quota/Config.h"
+
+#include "mozStorageHelper.h"
+#include "nsCOMPtr.h"
+#include "nscore.h"
+#include "nsHashKeys.h"
+#include "nsInterfaceHashtable.h"
+#include "nsString.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/NotNull.h"
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/dom/quota/ScopedLogExtraInfo.h"
+
+namespace mozilla::dom::quota {
+
+class CachingDatabaseConnection {
+ public:
+  class CachedStatement;
+
+  // A stack-only RAII wrapper that resets its borrowed statement when the
+  // wrapper goes out of scope. Note it's intentionally not declared MOZ_RAII,
+  // because it actually is used as a temporary in simple cases like
+  // `stmt.Borrow()->Execute()`. It also automatically exposes the current query
+  // to ScopedLogExtraInfo as "query" in builds where this mechanism is active.
+  class MOZ_STACK_CLASS BorrowedStatement : mozStorageStatementScoper {
+   public:
+    mozIStorageStatement& operator*() const;
+
+    MOZ_NONNULL_RETURN mozIStorageStatement* operator->() const
+        MOZ_NO_ADDREF_RELEASE_ON_RETURN;
+
+    BorrowedStatement(BorrowedStatement&& aOther) = default;
+
+    // No funny business allowed.
+    BorrowedStatement& operator=(BorrowedStatement&&) = delete;
+    BorrowedStatement(const BorrowedStatement&) = delete;
+    BorrowedStatement& operator=(const BorrowedStatement&) = delete;
+
+   private:
+    friend class CachedStatement;
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+    BorrowedStatement(NotNull<mozIStorageStatement*> aStatement,
+                      const nsACString& aQuery)
+        : mozStorageStatementScoper(aStatement),
+          mExtraInfo{ScopedLogExtraInfo::kTagQuery, aQuery} {}
+
+    ScopedLogExtraInfo mExtraInfo;
+#else
+    MOZ_IMPLICIT BorrowedStatement(NotNull<mozIStorageStatement*> aStatement)
+        : mozStorageStatementScoper(aStatement) {}
+#endif
+  };
+
+  class LazyStatement;
+
+  void AssertIsOnConnectionThread() const {
+#ifdef MOZ_THREAD_SAFETY_OWNERSHIP_CHECKS_SUPPORTED
+    mOwningThread->AssertOwnership("CachingDatabaseConnection not thread-safe");
+#endif
+  }
+
+  bool HasStorageConnection() const {
+    return static_cast<bool>(mStorageConnection);
+  }
+
+  mozIStorageConnection& MutableStorageConnection() const {
+    AssertIsOnConnectionThread();
+    MOZ_ASSERT(mStorageConnection);
+
+    return **mStorageConnection;
+  }
+
+  Result<CachedStatement, nsresult> GetCachedStatement(
+      const nsACString& aQuery);
+
+  Result<BorrowedStatement, nsresult> BorrowCachedStatement(
+      const nsACString& aQuery);
+
+  template <typename BindFunctor>
+  nsresult ExecuteCachedStatement(const nsACString& aQuery,
+                                  BindFunctor&& aBindFunctor) {
+    QM_TRY_INSPECT(const auto& stmt, BorrowCachedStatement(aQuery));
+    QM_TRY(std::forward<BindFunctor>(aBindFunctor)(*stmt));
+    QM_TRY(MOZ_TO_RESULT(stmt->Execute()));
+
+    return NS_OK;
+  }
+
+  nsresult ExecuteCachedStatement(const nsACString& aQuery);
+
+  template <typename BindFunctor>
+  Result<Maybe<BorrowedStatement>, nsresult>
+  BorrowAndExecuteSingleStepStatement(const nsACString& aQuery,
+                                      BindFunctor&& aBindFunctor);
+
+#ifdef DEBUG
+  ~CachingDatabaseConnection() {
+    MOZ_ASSERT(!mStorageConnection);
+    MOZ_ASSERT(!mCachedStatements.Count());
+  }
+#endif
+
+ protected:
+  explicit CachingDatabaseConnection(
+      MovingNotNull<nsCOMPtr<mozIStorageConnection>> aStorageConnection);
+
+  CachingDatabaseConnection() = default;
+
+  void LazyInit(
+      MovingNotNull<nsCOMPtr<mozIStorageConnection>> aStorageConnection);
+
+  void Close();
+
+ private:
+#ifdef MOZ_THREAD_SAFETY_OWNERSHIP_CHECKS_SUPPORTED
+  LazyInitializedOnce<const nsAutoOwningThread> mOwningThread;
+#endif
+
+  LazyInitializedOnceEarlyDestructible<
+      const NotNull<nsCOMPtr<mozIStorageConnection>>>
+      mStorageConnection;
+  nsInterfaceHashtable<nsCStringHashKey, mozIStorageStatement>
+      mCachedStatements;
+};
+
+class CachingDatabaseConnection::CachedStatement final {
+  friend class CachingDatabaseConnection;
+
+  nsCOMPtr<mozIStorageStatement> mStatement;
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  nsCString mQuery;
+#endif
+
+#ifdef DEBUG
+  CachingDatabaseConnection* mDEBUGConnection;
+#endif
+
+ public:
+#if defined(DEBUG) || defined(NS_BUILD_REFCNT_LOGGING)
+  CachedStatement();
+  ~CachedStatement();
+#else
+  CachedStatement() = default;
+#endif
+
+  void AssertIsOnConnectionThread() const;
+
+  explicit operator bool() const;
+
+  BorrowedStatement Borrow() const;
+
+ private:
+  // Only called by CachingDatabaseConnection.
+  CachedStatement(CachingDatabaseConnection* aConnection,
+                  nsCOMPtr<mozIStorageStatement> aStatement,
+                  const nsACString& aQuery);
+
+ public:
+#if defined(NS_BUILD_REFCNT_LOGGING)
+  CachedStatement(CachedStatement&& aOther)
+      : mStatement(std::move(aOther.mStatement))
+#  ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+        ,
+        mQuery(std::move(aOther.mQuery))
+#  endif
+#  ifdef DEBUG
+        ,
+        mDEBUGConnection(aOther.mDEBUGConnection)
+#  endif
+  {
+    MOZ_COUNT_CTOR(CachingDatabaseConnection::CachedStatement);
+  }
+#else
+  CachedStatement(CachedStatement&&) = default;
+#endif
+
+  CachedStatement& operator=(CachedStatement&&) = default;
+
+  // No funny business allowed.
+  CachedStatement(const CachedStatement&) = delete;
+  CachedStatement& operator=(const CachedStatement&) = delete;
+};
+
+class CachingDatabaseConnection::LazyStatement final {
+ public:
+  LazyStatement(CachingDatabaseConnection& aConnection,
+                const nsACString& aQueryString)
+      : mConnection{aConnection}, mQueryString{aQueryString} {}
+
+  Result<CachingDatabaseConnection::BorrowedStatement, nsresult> Borrow();
+
+  template <typename BindFunctor>
+  Result<Maybe<CachingDatabaseConnection::BorrowedStatement>, nsresult>
+  BorrowAndExecuteSingleStep(BindFunctor&& aBindFunctor) {
+    QM_TRY_UNWRAP(auto borrowedStatement, Borrow());
+
+    QM_TRY(std::forward<BindFunctor>(aBindFunctor)(*borrowedStatement));
+
+    QM_TRY_INSPECT(
+        const bool& hasResult,
+        MOZ_TO_RESULT_INVOKE_MEMBER(&*borrowedStatement, ExecuteStep));
+
+    return hasResult ? Some(std::move(borrowedStatement)) : Nothing{};
+  }
+
+ private:
+  Result<Ok, nsresult> Initialize();
+
+  CachingDatabaseConnection& mConnection;
+  const nsCString mQueryString;
+  CachingDatabaseConnection::CachedStatement mCachedStatement;
+};
+
+template <typename BindFunctor>
+Result<Maybe<CachingDatabaseConnection::BorrowedStatement>, nsresult>
+CachingDatabaseConnection::BorrowAndExecuteSingleStepStatement(
+    const nsACString& aQuery, BindFunctor&& aBindFunctor) {
+  return LazyStatement{*this, aQuery}.BorrowAndExecuteSingleStep(
+      std::forward<BindFunctor>(aBindFunctor));
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_CACHINGDATABASECONNECTION_H_
diff --git a/dom/quota/CanonicalQuotaObject.cpp b/dom/quota/CanonicalQuotaObject.cpp
new file mode 100644
index 0000000000..388f20e541
--- /dev/null
+++ b/dom/quota/CanonicalQuotaObject.cpp
@@ -0,0 +1,331 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "CanonicalQuotaObject.h"
+
+#include "GroupInfo.h"
+#include "GroupInfoPair.h"
+#include "mozilla/dom/StorageActivityService.h"
+#include "mozilla/dom/quota/AssertionsImpl.h"
+#include "mozilla/dom/quota/DirectoryLock.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+#include "mozilla/ipc/BackgroundParent.h"
+#include "OriginInfo.h"
+
+namespace mozilla::dom::quota {
+
+NS_IMETHODIMP_(MozExternalRefCountType) CanonicalQuotaObject::AddRef() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  if (!quotaManager) {
+    NS_ERROR("Null quota manager, this shouldn't happen, possible leak!");
+
+    return ++mRefCnt;
+  }
+
+  MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+  return ++mRefCnt;
+}
+
+NS_IMETHODIMP_(MozExternalRefCountType) CanonicalQuotaObject::Release() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  if (!quotaManager) {
+    NS_ERROR("Null quota manager, this shouldn't happen, possible leak!");
+
+    nsrefcnt count = --mRefCnt;
+    if (count == 0) {
+      mRefCnt = 1;
+      delete this;
+      return 0;
+    }
+
+    return mRefCnt;
+  }
+
+  {
+    MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+    --mRefCnt;
+
+    if (mRefCnt > 0) {
+      return mRefCnt;
+    }
+
+    if (mOriginInfo) {
+      mOriginInfo->mCanonicalQuotaObjects.Remove(mPath);
+    }
+  }
+
+  delete this;
+  return 0;
+}
+
+bool CanonicalQuotaObject::MaybeUpdateSize(int64_t aSize, bool aTruncate) {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+  return LockedMaybeUpdateSize(aSize, aTruncate);
+}
+
+bool CanonicalQuotaObject::IncreaseSize(int64_t aDelta) {
+  MOZ_ASSERT(aDelta >= 0);
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+  AssertNoOverflow(mSize, aDelta);
+  int64_t size = mSize + aDelta;
+
+  return LockedMaybeUpdateSize(size, /* aTruncate */ false);
+}
+
+void CanonicalQuotaObject::DisableQuotaCheck() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+  mQuotaCheckDisabled = true;
+}
+
+void CanonicalQuotaObject::EnableQuotaCheck() {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  MutexAutoLock lock(quotaManager->mQuotaMutex);
+
+  mQuotaCheckDisabled = false;
+}
+
+bool CanonicalQuotaObject::LockedMaybeUpdateSize(int64_t aSize,
+                                                 bool aTruncate) {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  quotaManager->mQuotaMutex.AssertCurrentThreadOwns();
+
+  if (mWritingDone == false && mOriginInfo) {
+    mWritingDone = true;
+    StorageActivityService::SendActivity(mOriginInfo->mOrigin);
+  }
+
+  if (mQuotaCheckDisabled) {
+    return true;
+  }
+
+  if (mSize == aSize) {
+    return true;
+  }
+
+  if (!mOriginInfo) {
+    mSize = aSize;
+    return true;
+  }
+
+  GroupInfo* groupInfo = mOriginInfo->mGroupInfo;
+  MOZ_ASSERT(groupInfo);
+
+  if (mSize > aSize) {
+    if (aTruncate) {
+      const int64_t delta = mSize - aSize;
+
+      AssertNoUnderflow(quotaManager->mTemporaryStorageUsage, delta);
+      quotaManager->mTemporaryStorageUsage -= delta;
+
+      if (!mOriginInfo->LockedPersisted()) {
+        AssertNoUnderflow(groupInfo->mUsage, delta);
+        groupInfo->mUsage -= delta;
+      }
+
+      AssertNoUnderflow(mOriginInfo->mUsage, delta);
+      mOriginInfo->mUsage -= delta;
+
+      MOZ_ASSERT(mOriginInfo->mClientUsages[mClientType].isSome());
+      AssertNoUnderflow(mOriginInfo->mClientUsages[mClientType].value(), delta);
+      mOriginInfo->mClientUsages[mClientType] =
+          Some(mOriginInfo->mClientUsages[mClientType].value() - delta);
+
+      mSize = aSize;
+    }
+    return true;
+  }
+
+  MOZ_ASSERT(mSize < aSize);
+
+  RefPtr<GroupInfo> complementaryGroupInfo =
+      groupInfo->mGroupInfoPair->LockedGetGroupInfo(
+          ComplementaryPersistenceType(groupInfo->mPersistenceType));
+
+  uint64_t delta = aSize - mSize;
+
+  AssertNoOverflow(mOriginInfo->mClientUsages[mClientType].valueOr(0), delta);
+  uint64_t newClientUsage =
+      mOriginInfo->mClientUsages[mClientType].valueOr(0) + delta;
+
+  AssertNoOverflow(mOriginInfo->mUsage, delta);
+  uint64_t newUsage = mOriginInfo->mUsage + delta;
+
+  // Temporary storage has no limit for origin usage (there's a group and the
+  // global limit though).
+
+  uint64_t newGroupUsage = groupInfo->mUsage;
+  if (!mOriginInfo->LockedPersisted()) {
+    AssertNoOverflow(groupInfo->mUsage, delta);
+    newGroupUsage += delta;
+
+    uint64_t groupUsage = groupInfo->mUsage;
+    if (complementaryGroupInfo) {
+      AssertNoOverflow(groupUsage, complementaryGroupInfo->mUsage);
+      groupUsage += complementaryGroupInfo->mUsage;
+    }
+
+    // Temporary storage has a hard limit for group usage (20 % of the global
+    // limit).
+    AssertNoOverflow(groupUsage, delta);
+    if (groupUsage + delta > quotaManager->GetGroupLimit()) {
+      return false;
+    }
+  }
+
+  AssertNoOverflow(quotaManager->mTemporaryStorageUsage, delta);
+  uint64_t newTemporaryStorageUsage =
+      quotaManager->mTemporaryStorageUsage + delta;
+
+  if (newTemporaryStorageUsage > quotaManager->mTemporaryStorageLimit) {
+    // This will block the thread without holding the lock while waitting.
+
+    AutoTArray<RefPtr<OriginDirectoryLock>, 10> locks;
+    uint64_t sizeToBeFreed;
+
+    if (::mozilla::ipc::IsOnBackgroundThread()) {
+      MutexAutoUnlock autoUnlock(quotaManager->mQuotaMutex);
+
+      sizeToBeFreed = quotaManager->CollectOriginsForEviction(delta, locks);
+    } else {
+      sizeToBeFreed =
+          quotaManager->LockedCollectOriginsForEviction(delta, locks);
+    }
+
+    if (!sizeToBeFreed) {
+      uint64_t usage = quotaManager->mTemporaryStorageUsage;
+
+      MutexAutoUnlock autoUnlock(quotaManager->mQuotaMutex);
+
+      quotaManager->NotifyStoragePressure(usage);
+
+      return false;
+    }
+
+    NS_ASSERTION(sizeToBeFreed >= delta, "Huh?");
+
+    {
+      MutexAutoUnlock autoUnlock(quotaManager->mQuotaMutex);
+
+      for (const auto& lock : locks) {
+        quotaManager->DeleteFilesForOrigin(lock->GetPersistenceType(),
+                                           lock->Origin());
+      }
+    }
+
+    // Relocked.
+
+    NS_ASSERTION(mOriginInfo, "How come?!");
+
+    for (const auto& lock : locks) {
+      MOZ_ASSERT(!(lock->GetPersistenceType() == groupInfo->mPersistenceType &&
+                   lock->Origin() == mOriginInfo->mOrigin),
+                 "Deleted itself!");
+
+      quotaManager->LockedRemoveQuotaForOrigin(lock->OriginMetadata());
+    }
+
+    // We unlocked and relocked several times so we need to recompute all the
+    // essential variables and recheck the group limit.
+
+    AssertNoUnderflow(aSize, mSize);
+    delta = aSize - mSize;
+
+    AssertNoOverflow(mOriginInfo->mClientUsages[mClientType].valueOr(0), delta);
+    newClientUsage = mOriginInfo->mClientUsages[mClientType].valueOr(0) + delta;
+
+    AssertNoOverflow(mOriginInfo->mUsage, delta);
+    newUsage = mOriginInfo->mUsage + delta;
+
+    newGroupUsage = groupInfo->mUsage;
+    if (!mOriginInfo->LockedPersisted()) {
+      AssertNoOverflow(groupInfo->mUsage, delta);
+      newGroupUsage += delta;
+
+      uint64_t groupUsage = groupInfo->mUsage;
+      if (complementaryGroupInfo) {
+        AssertNoOverflow(groupUsage, complementaryGroupInfo->mUsage);
+        groupUsage += complementaryGroupInfo->mUsage;
+      }
+
+      AssertNoOverflow(groupUsage, delta);
+      if (groupUsage + delta > quotaManager->GetGroupLimit()) {
+        // Unfortunately some other thread increased the group usage in the
+        // meantime and we are not below the group limit anymore.
+
+        // However, the origin eviction must be finalized in this case too.
+        MutexAutoUnlock autoUnlock(quotaManager->mQuotaMutex);
+
+        quotaManager->FinalizeOriginEviction(std::move(locks));
+
+        return false;
+      }
+    }
+
+    AssertNoOverflow(quotaManager->mTemporaryStorageUsage, delta);
+    newTemporaryStorageUsage = quotaManager->mTemporaryStorageUsage + delta;
+
+    NS_ASSERTION(
+        newTemporaryStorageUsage <= quotaManager->mTemporaryStorageLimit,
+        "How come?!");
+
+    // Ok, we successfully freed enough space and the operation can continue
+    // without throwing the quota error.
+    mOriginInfo->mClientUsages[mClientType] = Some(newClientUsage);
+
+    mOriginInfo->mUsage = newUsage;
+    if (!mOriginInfo->LockedPersisted()) {
+      groupInfo->mUsage = newGroupUsage;
+    }
+    quotaManager->mTemporaryStorageUsage = newTemporaryStorageUsage;
+    ;
+
+    // Some other thread could increase the size in the meantime, but no more
+    // than this one.
+    MOZ_ASSERT(mSize < aSize);
+    mSize = aSize;
+
+    // Finally, release IO thread only objects and allow next synchronized
+    // ops for the evicted origins.
+    MutexAutoUnlock autoUnlock(quotaManager->mQuotaMutex);
+
+    quotaManager->FinalizeOriginEviction(std::move(locks));
+
+    return true;
+  }
+
+  mOriginInfo->mClientUsages[mClientType] = Some(newClientUsage);
+
+  mOriginInfo->mUsage = newUsage;
+  if (!mOriginInfo->LockedPersisted()) {
+    groupInfo->mUsage = newGroupUsage;
+  }
+  quotaManager->mTemporaryStorageUsage = newTemporaryStorageUsage;
+
+  mSize = aSize;
+
+  return true;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/CanonicalQuotaObject.h b/dom/quota/CanonicalQuotaObject.h
new file mode 100644
index 0000000000..c47862f887
--- /dev/null
+++ b/dom/quota/CanonicalQuotaObject.h
@@ -0,0 +1,90 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_CANONICALQUOTAOBJECT_H_
+#define DOM_QUOTA_CANONICALQUOTAOBJECT_H_
+
+// Local includes
+#include "Client.h"
+
+// Global includes
+#include <cstdint>
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/dom/quota/Assertions.h"
+#include "mozilla/dom/quota/QuotaObject.h"
+#include "nsCOMPtr.h"
+#include "nsISupports.h"
+#include "nsStringFwd.h"
+
+// XXX Avoid including this here by moving function bodies to the cpp file.
+#include "mozilla/dom/quota/QuotaCommon.h"
+
+namespace mozilla::dom::quota {
+
+class OriginInfo;
+class QuotaManager;
+
+class CanonicalQuotaObject final : public QuotaObject {
+  friend class OriginInfo;
+  friend class QuotaManager;
+
+  class StoragePressureRunnable;
+
+ public:
+  NS_IMETHOD_(MozExternalRefCountType) AddRef() override;
+
+  NS_IMETHOD_(MozExternalRefCountType) Release() override;
+
+  const nsAString& Path() const override { return mPath; }
+
+  [[nodiscard]] bool MaybeUpdateSize(int64_t aSize, bool aTruncate) override;
+
+  bool IncreaseSize(int64_t aDelta) override;
+
+  void DisableQuotaCheck() override;
+
+  void EnableQuotaCheck() override;
+
+ private:
+  CanonicalQuotaObject(OriginInfo* aOriginInfo, Client::Type aClientType,
+                       const nsAString& aPath, int64_t aSize)
+      : QuotaObject(/* aIsRemote */ false),
+        mOriginInfo(aOriginInfo),
+        mPath(aPath),
+        mSize(aSize),
+        mClientType(aClientType),
+        mQuotaCheckDisabled(false),
+        mWritingDone(false) {
+    MOZ_COUNT_CTOR(CanonicalQuotaObject);
+  }
+
+  MOZ_COUNTED_DTOR(CanonicalQuotaObject)
+
+  already_AddRefed<QuotaObject> LockedAddRef() {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    ++mRefCnt;
+
+    RefPtr<QuotaObject> result = dont_AddRef(this);
+    return result.forget();
+  }
+
+  bool LockedMaybeUpdateSize(int64_t aSize, bool aTruncate);
+
+  mozilla::ThreadSafeAutoRefCnt mRefCnt;
+
+  OriginInfo* mOriginInfo;
+  nsString mPath;
+  int64_t mSize;
+  Client::Type mClientType;
+  bool mQuotaCheckDisabled;
+  bool mWritingDone;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_CANONICALQUOTAOBJECT_H_
diff --git a/dom/quota/CheckedUnsafePtr.h b/dom/quota/CheckedUnsafePtr.h
new file mode 100644
index 0000000000..70d18b4c7c
--- /dev/null
+++ b/dom/quota/CheckedUnsafePtr.h
@@ -0,0 +1,405 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Diagnostic class template that helps finding dangling pointers.
+
+#ifndef mozilla_CheckedUnsafePtr_h
+#define mozilla_CheckedUnsafePtr_h
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/DataMutex.h"
+#include "nsTArray.h"
+
+#include <cstddef>
+#include <type_traits>
+#include <utility>
+
+namespace mozilla {
+enum class CheckingSupport {
+  Disabled,
+  Enabled,
+};
+
+template <typename T>
+class CheckedUnsafePtr;
+
+namespace detail {
+class CheckedUnsafePtrBaseCheckingEnabled;
+
+struct CheckedUnsafePtrCheckData {
+  using Data = nsTArray<CheckedUnsafePtrBaseCheckingEnabled*>;
+
+  DataMutex<Data> mPtrs{"mozilla::SupportsCheckedUnsafePtr"};
+};
+
+class CheckedUnsafePtrBaseCheckingEnabled {
+  friend class CheckedUnsafePtrBaseAccess;
+
+ protected:
+  constexpr CheckedUnsafePtrBaseCheckingEnabled() = default;
+  CheckedUnsafePtrBaseCheckingEnabled(
+      const CheckedUnsafePtrBaseCheckingEnabled& aOther) = default;
+
+  // When copying an CheckedUnsafePtr, its mIsDangling member must be copied as
+  // well; otherwise the new copy might try to dereference a dangling pointer
+  // when destructed.
+  void CopyDanglingFlagIfAvailableFrom(
+      const CheckedUnsafePtrBaseCheckingEnabled& aOther) {
+    mIsDangling = aOther.mIsDangling;
+  }
+
+  template <typename Ptr>
+  using DisableForCheckedUnsafePtr = std::enable_if_t<
+      !std::is_base_of<CheckedUnsafePtrBaseCheckingEnabled, Ptr>::value>;
+
+  // When constructing an CheckedUnsafePtr from a different kind of pointer it's
+  // not possible to determine whether it's dangling; therefore it's undefined
+  // behavior to construct one from a dangling pointer, and we assume that any
+  // CheckedUnsafePtr thus constructed is not dangling.
+  template <typename Ptr>
+  DisableForCheckedUnsafePtr<Ptr> CopyDanglingFlagIfAvailableFrom(const Ptr&) {}
+
+  template <typename F>
+  void WithCheckedUnsafePtrsImpl(CheckedUnsafePtrCheckData* const aRawPtr,
+                                 F&& aClosure) {
+    if (!mIsDangling && aRawPtr) {
+      const auto CheckedUnsafePtrs = aRawPtr->mPtrs.Lock();
+      aClosure(this, *CheckedUnsafePtrs);
+    }
+  }
+
+ private:
+  bool mIsDangling = false;
+};
+
+class CheckedUnsafePtrBaseAccess {
+ protected:
+  static void SetDanglingFlag(CheckedUnsafePtrBaseCheckingEnabled& aBase) {
+    aBase.mIsDangling = true;
+  }
+};
+
+template <typename T, CheckingSupport = T::SupportsChecking::value>
+class CheckedUnsafePtrBase;
+
+template <typename T, typename U, typename S = std::nullptr_t>
+using EnableIfCompatible = std::enable_if_t<
+    std::is_base_of<
+        T, std::remove_reference_t<decltype(*std::declval<U>())>>::value,
+    S>;
+
+template <typename T>
+class CheckedUnsafePtrBase<T, CheckingSupport::Enabled>
+    : detail::CheckedUnsafePtrBaseCheckingEnabled {
+ public:
+  MOZ_IMPLICIT constexpr CheckedUnsafePtrBase(const std::nullptr_t = nullptr)
+      : mRawPtr(nullptr) {}
+
+  template <typename U, typename = EnableIfCompatible<T, U>>
+  MOZ_IMPLICIT CheckedUnsafePtrBase(const U& aPtr) {
+    Set(aPtr);
+  }
+
+  CheckedUnsafePtrBase(const CheckedUnsafePtrBase& aOther) {
+    Set(aOther.Downcast());
+  }
+
+  ~CheckedUnsafePtrBase() { Reset(); }
+
+  CheckedUnsafePtr<T>& operator=(const std::nullptr_t) {
+    Reset();
+    return Downcast();
+  }
+
+  template <typename U>
+  EnableIfCompatible<T, U, CheckedUnsafePtr<T>&> operator=(const U& aPtr) {
+    Replace(aPtr);
+    return Downcast();
+  }
+
+  CheckedUnsafePtrBase& operator=(const CheckedUnsafePtrBase& aOther) {
+    if (&aOther != this) {
+      Replace(aOther.Downcast());
+    }
+    return Downcast();
+  }
+
+  constexpr T* get() const { return mRawPtr; }
+
+ private:
+  template <typename U, CheckingSupport>
+  friend class CheckedUnsafePtrBase;
+
+  CheckedUnsafePtr<T>& Downcast() {
+    return static_cast<CheckedUnsafePtr<T>&>(*this);
+  }
+  const CheckedUnsafePtr<T>& Downcast() const {
+    return static_cast<const CheckedUnsafePtr<T>&>(*this);
+  }
+
+  using Base = detail::CheckedUnsafePtrBaseCheckingEnabled;
+
+  template <typename U>
+  void Replace(const U& aPtr) {
+    Reset();
+    Set(aPtr);
+  }
+
+  void Reset() {
+    WithCheckedUnsafePtrs(
+        [](Base* const aSelf,
+           detail::CheckedUnsafePtrCheckData::Data& aCheckedUnsafePtrs) {
+          const auto index = aCheckedUnsafePtrs.IndexOf(aSelf);
+          aCheckedUnsafePtrs.UnorderedRemoveElementAt(index);
+        });
+    mRawPtr = nullptr;
+  }
+
+  template <typename U>
+  void Set(const U& aPtr) {
+    this->CopyDanglingFlagIfAvailableFrom(aPtr);
+    mRawPtr = &*aPtr;
+    WithCheckedUnsafePtrs(
+        [](Base* const aSelf,
+           detail::CheckedUnsafePtrCheckData::Data& aCheckedUnsafePtrs) {
+          aCheckedUnsafePtrs.AppendElement(aSelf);
+        });
+  }
+
+  template <typename F>
+  void WithCheckedUnsafePtrs(F&& aClosure) {
+    this->WithCheckedUnsafePtrsImpl(mRawPtr, std::forward<F>(aClosure));
+  }
+
+  T* mRawPtr;
+};
+
+template <typename T>
+class CheckedUnsafePtrBase<T, CheckingSupport::Disabled> {
+ public:
+  MOZ_IMPLICIT constexpr CheckedUnsafePtrBase(const std::nullptr_t = nullptr)
+      : mRawPtr(nullptr) {}
+
+  template <typename U, typename = EnableIfCompatible<T, U>>
+  MOZ_IMPLICIT constexpr CheckedUnsafePtrBase(const U& aPtr) : mRawPtr(aPtr) {}
+
+  constexpr CheckedUnsafePtr<T>& operator=(const std::nullptr_t) {
+    mRawPtr = nullptr;
+    return Downcast();
+  }
+
+  template <typename U>
+  constexpr EnableIfCompatible<T, U, CheckedUnsafePtr<T>&> operator=(
+      const U& aPtr) {
+    mRawPtr = aPtr;
+    return Downcast();
+  }
+
+  constexpr T* get() const { return mRawPtr; }
+
+ private:
+  constexpr CheckedUnsafePtr<T>& Downcast() {
+    return static_cast<CheckedUnsafePtr<T>&>(*this);
+  }
+
+  T* mRawPtr;
+};
+}  // namespace detail
+
+class CheckingPolicyAccess {
+ protected:
+  template <typename CheckingPolicy>
+  static void NotifyCheckFailure(CheckingPolicy& aPolicy) {
+    aPolicy.NotifyCheckFailure();
+  }
+};
+
+template <typename Derived>
+class CheckCheckedUnsafePtrs : private CheckingPolicyAccess,
+                               private detail::CheckedUnsafePtrBaseAccess {
+ public:
+  using SupportsChecking =
+      std::integral_constant<CheckingSupport, CheckingSupport::Enabled>;
+
+ protected:
+  static constexpr bool ShouldCheck() {
+    static_assert(
+        std::is_base_of<CheckCheckedUnsafePtrs, Derived>::value,
+        "cannot instantiate with a type that's not a subclass of this class");
+    return true;
+  }
+
+  void Check(detail::CheckedUnsafePtrCheckData::Data& aCheckedUnsafePtrs) {
+    if (!aCheckedUnsafePtrs.IsEmpty()) {
+      for (auto* const aCheckedUnsafePtrBase : aCheckedUnsafePtrs) {
+        SetDanglingFlag(*aCheckedUnsafePtrBase);
+      }
+      NotifyCheckFailure(*static_cast<Derived*>(this));
+    }
+  }
+};
+
+class CrashOnDanglingCheckedUnsafePtr
+    : public CheckCheckedUnsafePtrs<CrashOnDanglingCheckedUnsafePtr> {
+  friend class mozilla::CheckingPolicyAccess;
+  void NotifyCheckFailure() { MOZ_CRASH("Found dangling CheckedUnsafePtr"); }
+};
+
+struct DoNotCheckCheckedUnsafePtrs {
+  using SupportsChecking =
+      std::integral_constant<CheckingSupport, CheckingSupport::Disabled>;
+};
+
+namespace detail {
+// Template parameter CheckingSupport controls the inclusion of
+// CheckedUnsafePtrCheckData as a subobject of instantiations of
+// SupportsCheckedUnsafePtr, ensuring that choosing a policy without checking
+// support incurs no size overhead.
+template <typename CheckingPolicy,
+          CheckingSupport = CheckingPolicy::SupportsChecking::value>
+class SupportCheckedUnsafePtrImpl;
+
+template <typename CheckingPolicy>
+class SupportCheckedUnsafePtrImpl<CheckingPolicy, CheckingSupport::Disabled>
+    : public CheckingPolicy {
+ protected:
+  template <typename... Args>
+  explicit SupportCheckedUnsafePtrImpl(Args&&... aArgs)
+      : CheckingPolicy(std::forward<Args>(aArgs)...) {}
+};
+
+template <typename CheckingPolicy>
+class SupportCheckedUnsafePtrImpl<CheckingPolicy, CheckingSupport::Enabled>
+    : public CheckedUnsafePtrCheckData, public CheckingPolicy {
+  template <typename T>
+  friend class CheckedUnsafePtr;
+
+ protected:
+  template <typename... Args>
+  explicit SupportCheckedUnsafePtrImpl(Args&&... aArgs)
+      : CheckingPolicy(std::forward<Args>(aArgs)...) {}
+
+  ~SupportCheckedUnsafePtrImpl() {
+    if (this->ShouldCheck()) {
+      const auto ptrs = mPtrs.Lock();
+      this->Check(*ptrs);
+    }
+  }
+};
+
+struct SupportsCheckedUnsafePtrTag {};
+}  // namespace detail
+
+template <typename Condition,
+          typename CheckingPolicy = CrashOnDanglingCheckedUnsafePtr>
+using CheckIf = std::conditional_t<Condition::value, CheckingPolicy,
+                                   DoNotCheckCheckedUnsafePtrs>;
+
+using DiagnosticAssertEnabled = std::integral_constant<bool,
+#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
+                                                       true
+#else
+                                                       false
+#endif
+                                                       >;
+
+// A T class that publicly inherits from an instantiation of
+// SupportsCheckedUnsafePtr and its subclasses can be pointed to by smart
+// pointers of type CheckedUnsafePtr<T>. Whenever such a smart pointer is
+// created, its existence is tracked by the pointee according to its
+// CheckingPolicy. When the pointee goes out of scope it then uses the its
+// CheckingPolicy to verify that no CheckedUnsafePtr pointers are left pointing
+// to it.
+//
+// The CheckingPolicy type is used to control the kind of verification that
+// happen at the end of the object's lifetime. By default, debug builds always
+// check for dangling CheckedUnsafePtr pointers and assert that none are found,
+// while release builds forgo all checks. (Release builds incur no size or
+// runtime penalties compared to bare pointers.)
+template <typename CheckingPolicy>
+class SupportsCheckedUnsafePtr
+    : public detail::SupportCheckedUnsafePtrImpl<CheckingPolicy>,
+      public detail::SupportsCheckedUnsafePtrTag {
+ public:
+  template <typename... Args>
+  explicit SupportsCheckedUnsafePtr(Args&&... aArgs)
+      : detail::SupportCheckedUnsafePtrImpl<CheckingPolicy>(
+            std::forward<Args>(aArgs)...) {}
+};
+
+// CheckedUnsafePtr<T> is a smart pointer class that helps detect dangling
+// pointers in cases where such pointers are not allowed. In order to use it,
+// the pointee T must publicly inherit from an instantiation of
+// SupportsCheckedUnsafePtr. An CheckedUnsafePtr<T> can be used anywhere a T*
+// can be used, has the same size, and imposes no additional thread-safety
+// restrictions.
+template <typename T>
+class CheckedUnsafePtr : public detail::CheckedUnsafePtrBase<T> {
+  static_assert(
+      std::is_base_of<detail::SupportsCheckedUnsafePtrTag, T>::value,
+      "type T must be derived from instantiation of SupportsCheckedUnsafePtr");
+
+ public:
+  using detail::CheckedUnsafePtrBase<T>::CheckedUnsafePtrBase;
+  using detail::CheckedUnsafePtrBase<T>::get;
+
+  constexpr T* operator->() const { return get(); }
+
+  constexpr T& operator*() const { return *get(); }
+
+  MOZ_IMPLICIT constexpr operator T*() const { return get(); }
+
+  template <typename U>
+  constexpr bool operator==(
+      detail::EnableIfCompatible<T, U, const U&> aRhs) const {
+    return get() == aRhs.get();
+  }
+
+  template <typename U>
+  friend constexpr bool operator==(
+      detail::EnableIfCompatible<T, U, const U&> aLhs,
+      const CheckedUnsafePtr& aRhs) {
+    return aRhs == aLhs;
+  }
+
+  template <typename U>
+  constexpr bool operator!=(
+      detail::EnableIfCompatible<T, U, const U&> aRhs) const {
+    return !(*this == aRhs);
+  }
+
+  template <typename U>
+  friend constexpr bool operator!=(
+      detail::EnableIfCompatible<T, U, const U&> aLhs,
+      const CheckedUnsafePtr& aRhs) {
+    return aRhs != aLhs;
+  }
+};
+
+}  // namespace mozilla
+
+// nsTArray<T> requires by default that T can be safely moved with std::memmove.
+// Since CheckedUnsafePtr<T> has a non-trivial copy constructor, it has to opt
+// into nsTArray<T> using them.
+template <typename T>
+struct nsTArray_RelocationStrategy<mozilla::CheckedUnsafePtr<T>> {
+  using Type = std::conditional_t<
+      T::SupportsChecking::value == mozilla::CheckingSupport::Enabled,
+      nsTArray_RelocateUsingMoveConstructor<mozilla::CheckedUnsafePtr<T>>,
+      nsTArray_RelocateUsingMemutils>;
+};
+
+template <typename T>
+struct nsTArray_RelocationStrategy<
+    mozilla::NotNull<mozilla::CheckedUnsafePtr<T>>> {
+  using Type =
+      std::conditional_t<T::SupportsChecking::value ==
+                             mozilla::CheckingSupport::Enabled,
+                         nsTArray_RelocateUsingMoveConstructor<
+                             mozilla::NotNull<mozilla::CheckedUnsafePtr<T>>>,
+                         nsTArray_RelocateUsingMemutils>;
+};
+
+#endif  // mozilla_CheckedUnsafePtr_h
diff --git a/dom/quota/CipherStrategy.h b/dom/quota/CipherStrategy.h
new file mode 100644
index 0000000000..495bdb7528
--- /dev/null
+++ b/dom/quota/CipherStrategy.h
@@ -0,0 +1,42 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_CipherStrategy_h
+#define mozilla_dom_quota_CipherStrategy_h
+
+namespace mozilla::dom::quota {
+
+enum class CipherMode { Encrypt, Decrypt };
+
+// An implementation of the CipherStrategy concept must provide the following
+// data members:
+//
+//   static constexpr size_t BlockPrefixLength;
+//   static constexpr size_t BasicBlockSize;
+//
+// It must provide the following member types:
+//
+//   KeyType
+//   BlockPrefixType, which must be an InputRange of type uint8_t and a
+//                    SizedRange of size BlockPrefixLength
+//
+// It must provide the following member functions with compatible signatures:
+//
+//   static Result<KeyType, nsresult> GenerateKey();
+//
+//   nsresult Cipher(const CipherMode aMode, const KeyType& aKey,
+//                   Span<uint8_t> aIv, Span<const uint8_t> aIn,
+//                   Span<uint8_t> aOut);
+//
+//   BlockPrefixType MakeBlockPrefix();
+//
+//   Span<const uint8_t> SerializeKey(const KeyType& aKey);
+//
+//   KeyType DeserializeKey(const Span<const uint8_t>& aSerializedKey);
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/Client.cpp b/dom/quota/Client.cpp
new file mode 100644
index 0000000000..87da8815cc
--- /dev/null
+++ b/dom/quota/Client.cpp
@@ -0,0 +1,299 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Client.h"
+
+// Global includes
+#include "mozilla/ipc/BackgroundParent.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+
+namespace mozilla::dom::quota {
+
+using mozilla::ipc::AssertIsOnBackgroundThread;
+using mozilla::ipc::IsOnBackgroundThread;
+
+namespace {
+
+const char kIDBPrefix = 'I';
+const char kDOMCachePrefix = 'C';
+const char kSDBPrefix = 'S';
+const char kFILESYSTEMPrefix = 'F';
+const char kLSPrefix = 'L';
+
+template <Client::Type type>
+struct ClientTypeTraits;
+
+template <>
+struct ClientTypeTraits<Client::Type::IDB> {
+  template <typename T>
+  static void To(T& aData) {
+    aData.AssignLiteral(IDB_DIRECTORY_NAME);
+  }
+
+  static void To(char& aData) { aData = kIDBPrefix; }
+
+  template <typename T>
+  static bool From(const T& aData) {
+    return aData.EqualsLiteral(IDB_DIRECTORY_NAME);
+  }
+
+  static bool From(char aData) { return aData == kIDBPrefix; }
+};
+
+template <>
+struct ClientTypeTraits<Client::Type::DOMCACHE> {
+  template <typename T>
+  static void To(T& aData) {
+    aData.AssignLiteral(DOMCACHE_DIRECTORY_NAME);
+  }
+
+  static void To(char& aData) { aData = kDOMCachePrefix; }
+
+  template <typename T>
+  static bool From(const T& aData) {
+    return aData.EqualsLiteral(DOMCACHE_DIRECTORY_NAME);
+  }
+
+  static bool From(char aData) { return aData == kDOMCachePrefix; }
+};
+
+template <>
+struct ClientTypeTraits<Client::Type::SDB> {
+  template <typename T>
+  static void To(T& aData) {
+    aData.AssignLiteral(SDB_DIRECTORY_NAME);
+  }
+
+  static void To(char& aData) { aData = kSDBPrefix; }
+
+  template <typename T>
+  static bool From(const T& aData) {
+    return aData.EqualsLiteral(SDB_DIRECTORY_NAME);
+  }
+
+  static bool From(char aData) { return aData == kSDBPrefix; }
+};
+
+template <>
+struct ClientTypeTraits<Client::Type::FILESYSTEM> {
+  template <typename T>
+  static void To(T& aData) {
+    aData.AssignLiteral(FILESYSTEM_DIRECTORY_NAME);
+  }
+
+  static void To(char& aData) { aData = kFILESYSTEMPrefix; }
+
+  template <typename T>
+  static bool From(const T& aData) {
+    return aData.EqualsLiteral(FILESYSTEM_DIRECTORY_NAME);
+  }
+
+  static bool From(char aData) { return aData == kFILESYSTEMPrefix; }
+};
+
+template <>
+struct ClientTypeTraits<Client::Type::LS> {
+  template <typename T>
+  static void To(T& aData) {
+    aData.AssignLiteral(LS_DIRECTORY_NAME);
+  }
+
+  static void To(char& aData) { aData = kLSPrefix; }
+
+  template <typename T>
+  static bool From(const T& aData) {
+    return aData.EqualsLiteral(LS_DIRECTORY_NAME);
+  }
+
+  static bool From(char aData) { return aData == kLSPrefix; }
+};
+
+template <typename T>
+bool TypeTo_impl(Client::Type aType, T& aData) {
+  switch (aType) {
+    case Client::IDB:
+      ClientTypeTraits<Client::Type::IDB>::To(aData);
+      return true;
+
+    case Client::DOMCACHE:
+      ClientTypeTraits<Client::Type::DOMCACHE>::To(aData);
+      return true;
+
+    case Client::SDB:
+      ClientTypeTraits<Client::Type::SDB>::To(aData);
+      return true;
+
+    case Client::FILESYSTEM:
+      ClientTypeTraits<Client::Type::FILESYSTEM>::To(aData);
+      return true;
+
+    case Client::LS:
+      if (CachedNextGenLocalStorageEnabled()) {
+        ClientTypeTraits<Client::Type::LS>::To(aData);
+        return true;
+      }
+      [[fallthrough]];
+
+    case Client::TYPE_MAX:
+    default:
+      return false;
+  }
+
+  MOZ_CRASH("Should never get here!");
+}
+
+template <typename T>
+bool TypeFrom_impl(const T& aData, Client::Type& aType) {
+  if (ClientTypeTraits<Client::Type::IDB>::From(aData)) {
+    aType = Client::IDB;
+    return true;
+  }
+
+  if (ClientTypeTraits<Client::Type::DOMCACHE>::From(aData)) {
+    aType = Client::DOMCACHE;
+    return true;
+  }
+
+  if (ClientTypeTraits<Client::Type::SDB>::From(aData)) {
+    aType = Client::SDB;
+    return true;
+  }
+
+  if (ClientTypeTraits<Client::Type::FILESYSTEM>::From(aData)) {
+    aType = Client::FILESYSTEM;
+    return true;
+  }
+
+  if (CachedNextGenLocalStorageEnabled() &&
+      ClientTypeTraits<Client::Type::LS>::From(aData)) {
+    aType = Client::LS;
+    return true;
+  }
+
+  return false;
+}
+
+void BadType() { MOZ_CRASH("Bad client type value!"); }
+
+}  // namespace
+
+// static
+bool Client::IsValidType(Type aType) {
+  switch (aType) {
+    case Client::IDB:
+    case Client::DOMCACHE:
+    case Client::SDB:
+    case Client::FILESYSTEM:
+      return true;
+
+    case Client::LS:
+      if (CachedNextGenLocalStorageEnabled()) {
+        return true;
+      }
+      [[fallthrough]];
+
+    default:
+      return false;
+  }
+}
+
+// static
+bool Client::TypeToText(Type aType, nsAString& aText, const fallible_t&) {
+  nsString text;
+  if (!TypeTo_impl(aType, text)) {
+    return false;
+  }
+  aText = text;
+  return true;
+}
+
+// static
+nsAutoString Client::TypeToString(Type aType) {
+  nsAutoString res;
+  if (!TypeTo_impl(aType, res)) {
+    BadType();
+  }
+  return res;
+}
+
+// static
+nsAutoCString Client::TypeToText(Type aType) {
+  nsAutoCString res;
+  if (!TypeTo_impl(aType, res)) {
+    BadType();
+  }
+  return res;
+}
+
+// static
+bool Client::TypeFromText(const nsAString& aText, Type& aType,
+                          const fallible_t&) {
+  Type type;
+  if (!TypeFrom_impl(aText, type)) {
+    return false;
+  }
+  aType = type;
+  return true;
+}
+
+// static
+Client::Type Client::TypeFromText(const nsACString& aText) {
+  Type type;
+  if (!TypeFrom_impl(aText, type)) {
+    BadType();
+  }
+  return type;
+}
+
+// static
+char Client::TypeToPrefix(Type aType) {
+  char prefix;
+  if (!TypeTo_impl(aType, prefix)) {
+    BadType();
+  }
+  return prefix;
+}
+
+// static
+bool Client::TypeFromPrefix(char aPrefix, Type& aType, const fallible_t&) {
+  Type type;
+  if (!TypeFrom_impl(aPrefix, type)) {
+    return false;
+  }
+  aType = type;
+  return true;
+}
+
+bool Client::InitiateShutdownWorkThreads() {
+  AssertIsOnBackgroundThread();
+
+  QuotaManager::MaybeRecordQuotaClientShutdownStep(GetType(), "starting"_ns);
+
+  InitiateShutdown();
+
+  return IsShutdownCompleted();
+}
+
+void Client::FinalizeShutdownWorkThreads() {
+  QuotaManager::MaybeRecordQuotaClientShutdownStep(GetType(), "completed"_ns);
+
+  FinalizeShutdown();
+}
+
+// static
+bool Client::IsShuttingDownOnBackgroundThread() {
+  MOZ_ASSERT(IsOnBackgroundThread());
+  return QuotaManager::IsShuttingDown();
+}
+
+// static
+bool Client::IsShuttingDownOnNonBackgroundThread() {
+  MOZ_ASSERT(!IsOnBackgroundThread());
+  return QuotaManager::IsShuttingDown();
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/Client.h b/dom/quota/Client.h
new file mode 100644
index 0000000000..8a6f0a9548
--- /dev/null
+++ b/dom/quota/Client.h
@@ -0,0 +1,191 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_client_h__
+#define mozilla_dom_quota_client_h__
+
+#include "ErrorList.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/Result.h"
+#include "mozilla/dom/ipc/IdType.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "nsHashKeys.h"
+#include "nsISupports.h"
+#include "nsStringFwd.h"
+#include "nsTHashSet.h"
+
+// XXX Remove this dependency.
+#include "mozilla/dom/LocalStorageCommon.h"
+
+class nsIFile;
+
+#define IDB_DIRECTORY_NAME "idb"
+#define DOMCACHE_DIRECTORY_NAME "cache"
+#define SDB_DIRECTORY_NAME "sdb"
+#define FILESYSTEM_DIRECTORY_NAME "fs"
+#define LS_DIRECTORY_NAME "ls"
+
+// Deprecated
+#define ASMJSCACHE_DIRECTORY_NAME "asmjs"
+
+namespace mozilla::dom {
+template <typename T>
+struct Nullable;
+}
+
+namespace mozilla::dom::quota {
+
+struct OriginMetadata;
+class OriginScope;
+class QuotaManager;
+class UsageInfo;
+
+// An abstract interface for quota manager clients.
+// Each storage API must provide an implementation of this interface in order
+// to participate in centralized quota and storage handling.
+class Client {
+ public:
+  using AtomicBool = Atomic<bool>;
+
+  enum Type {
+    IDB = 0,
+    // APPCACHE,
+    DOMCACHE,
+    SDB,
+    FILESYSTEM,
+    LS,
+    TYPE_MAX
+  };
+
+  class DirectoryLockIdTable final {
+    nsTHashSet<uint64_t> mIds;
+
+   public:
+    void Put(const int64_t aId) { mIds.Insert(aId); }
+
+    bool Has(const int64_t aId) const { return mIds.Contains(aId); }
+
+    bool Filled() const { return mIds.Count(); }
+  };
+
+  static Type TypeMax() {
+    if (NextGenLocalStorageEnabled()) {
+      return TYPE_MAX;
+    }
+    return LS;
+  }
+
+  static bool IsValidType(Type aType);
+
+  static bool TypeToText(Type aType, nsAString& aText, const fallible_t&);
+
+  // TODO: Rename other similar methods to use String/CString instead of Text.
+  static nsAutoString TypeToString(Type aType);
+
+  static nsAutoCString TypeToText(Type aType);
+
+  static bool TypeFromText(const nsAString& aText, Type& aType,
+                           const fallible_t&);
+
+  static Type TypeFromText(const nsACString& aText);
+
+  static char TypeToPrefix(Type aType);
+
+  static bool TypeFromPrefix(char aPrefix, Type& aType, const fallible_t&);
+
+  static bool IsDeprecatedClient(const nsAString& aText) {
+    return aText.EqualsLiteral(ASMJSCACHE_DIRECTORY_NAME);
+  }
+
+  template <typename T>
+  static bool IsLockForObjectContainedInLockTable(
+      const T& aObject, const DirectoryLockIdTable& aIds);
+
+  template <typename T>
+  static bool IsLockForObjectAcquiredAndContainedInLockTable(
+      const T& aObject, const DirectoryLockIdTable& aIds);
+
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  virtual Type GetType() = 0;
+
+  // Methods which are called on the IO thread.
+  virtual nsresult UpgradeStorageFrom1_0To2_0(nsIFile* aDirectory) {
+    return NS_OK;
+  }
+
+  virtual nsresult UpgradeStorageFrom2_0To2_1(nsIFile* aDirectory) {
+    return NS_OK;
+  }
+
+  virtual nsresult UpgradeStorageFrom2_1To2_2(nsIFile* aDirectory) {
+    return NS_OK;
+  }
+
+  virtual Result<UsageInfo, nsresult> InitOrigin(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      const AtomicBool& aCanceled) = 0;
+
+  virtual nsresult InitOriginWithoutTracking(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      const AtomicBool& aCanceled) = 0;
+
+  virtual Result<UsageInfo, nsresult> GetUsageForOrigin(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      const AtomicBool& aCanceled) = 0;
+
+  // This method is called when origins are about to be cleared
+  // (except the case when clearing is triggered by the origin eviction).
+  virtual nsresult AboutToClearOrigins(
+      const Nullable<PersistenceType>& aPersistenceType,
+      const OriginScope& aOriginScope) {
+    return NS_OK;
+  }
+
+  virtual void OnOriginClearCompleted(PersistenceType aPersistenceType,
+                                      const nsACString& aOrigin) = 0;
+
+  virtual void ReleaseIOThreadObjects() = 0;
+
+  // Methods which are called on the background thread.
+  virtual void AbortOperationsForLocks(
+      const DirectoryLockIdTable& aDirectoryLockIds) = 0;
+
+  virtual void AbortOperationsForProcess(ContentParentId aContentParentId) = 0;
+
+  virtual void AbortAllOperations() = 0;
+
+  virtual void StartIdleMaintenance() = 0;
+
+  virtual void StopIdleMaintenance() = 0;
+
+  // Both variants just check for QuotaManager::IsShuttingDown()
+  // but assert to be on the right thread.
+  // They must not be used for re-entrance checks.
+  // Deprecated: This distinction is not needed anymore.
+  // QuotaClients should call QuotaManager::IsShuttingDown instead.
+  static bool IsShuttingDownOnBackgroundThread();
+  static bool IsShuttingDownOnNonBackgroundThread();
+
+  // Returns true if there is work that needs to be waited for.
+  bool InitiateShutdownWorkThreads();
+  void FinalizeShutdownWorkThreads();
+
+  virtual nsCString GetShutdownStatus() const = 0;
+  virtual bool IsShutdownCompleted() const = 0;
+  virtual void ForceKillActors() = 0;
+
+ private:
+  virtual void InitiateShutdown() = 0;
+  virtual void FinalizeShutdown() = 0;
+
+ protected:
+  virtual ~Client() = default;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_client_h__
diff --git a/dom/quota/ClientImpl.h b/dom/quota/ClientImpl.h
new file mode 100644
index 0000000000..9602345e5d
--- /dev/null
+++ b/dom/quota/ClientImpl.h
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_CLIENTIMPL_H_
+#define DOM_QUOTA_CLIENTIMPL_H_
+
+#include "mozilla/dom/quota/DirectoryLock.h"
+
+namespace mozilla::dom::quota {
+
+// static
+template <typename T>
+bool Client::IsLockForObjectContainedInLockTable(
+    const T& aObject, const DirectoryLockIdTable& aIds) {
+  const auto& maybeDirectoryLock = aObject.MaybeDirectoryLockRef();
+
+  MOZ_ASSERT(maybeDirectoryLock.isSome());
+
+  return aIds.Has(maybeDirectoryLock->Id());
+}
+
+// static
+template <typename T>
+bool Client::IsLockForObjectAcquiredAndContainedInLockTable(
+    const T& aObject, const DirectoryLockIdTable& aIds) {
+  const auto& maybeDirectoryLock = aObject.MaybeDirectoryLockRef();
+
+  return maybeDirectoryLock && aIds.Has(maybeDirectoryLock->Id());
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_CLIENTIMPL_H_
diff --git a/dom/quota/ClientUsageArray.cpp b/dom/quota/ClientUsageArray.cpp
new file mode 100644
index 0000000000..f0c8095b1c
--- /dev/null
+++ b/dom/quota/ClientUsageArray.cpp
@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ClientUsageArray.h"
+
+#include "mozilla/dom/quota/QuotaManager.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+
+namespace mozilla::dom::quota {
+
+void ClientUsageArray::Serialize(nsACString& aText) const {
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  bool first = true;
+
+  for (Client::Type type : quotaManager->AllClientTypes()) {
+    const Maybe<uint64_t>& clientUsage = ElementAt(type);
+    if (clientUsage.isSome()) {
+      if (first) {
+        first = false;
+      } else {
+        aText.Append(" ");
+      }
+
+      aText.Append(Client::TypeToPrefix(type));
+      aText.AppendInt(clientUsage.value());
+    }
+  }
+}
+
+nsresult ClientUsageArray::Deserialize(const nsACString& aText) {
+  for (const auto& token :
+       nsCCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing>(aText, ' ')
+           .ToRange()) {
+    QM_TRY(OkIf(token.Length() >= 2), NS_ERROR_FAILURE);
+
+    Client::Type clientType;
+    QM_TRY(OkIf(Client::TypeFromPrefix(token.First(), clientType, fallible)),
+           NS_ERROR_FAILURE);
+
+    nsresult rv;
+    const uint64_t usage = Substring(token, 1).ToInteger64(&rv);
+    QM_TRY(MOZ_TO_RESULT(rv));
+
+    ElementAt(clientType) = Some(usage);
+  }
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/ClientUsageArray.h b/dom/quota/ClientUsageArray.h
new file mode 100644
index 0000000000..3b57656143
--- /dev/null
+++ b/dom/quota/ClientUsageArray.h
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_CLIENTUSAGEARAY_H_
+#define DOM_QUOTA_CLIENTUSAGEARAY_H_
+
+#include <cstdint>
+#include "mozilla/Maybe.h"
+#include "mozilla/dom/quota/Client.h"
+
+namespace mozilla::dom::quota {
+
+// XXX Change this not to derive from AutoTArray.
+class ClientUsageArray final
+    : public AutoTArray<Maybe<uint64_t>, Client::TYPE_MAX> {
+ public:
+  ClientUsageArray() { SetLength(Client::TypeMax()); }
+
+  void Serialize(nsACString& aText) const;
+
+  nsresult Deserialize(const nsACString& aText);
+
+  ClientUsageArray Clone() const {
+    ClientUsageArray res;
+    res.Assign(*this);
+    return res;
+  }
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_CLIENTUSAGEARAY_H_
diff --git a/dom/quota/CommonMetadata.h b/dom/quota/CommonMetadata.h
new file mode 100644
index 0000000000..094c965195
--- /dev/null
+++ b/dom/quota/CommonMetadata.h
@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_COMMONMETADATA_H_
+#define DOM_QUOTA_COMMONMETADATA_H_
+
+#include <utility>
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "nsString.h"
+
+namespace mozilla::dom::quota {
+
+struct PrincipalMetadata {
+  nsCString mSuffix;
+  nsCString mGroup;
+  nsCString mOrigin;
+
+  // These explicit constructors exist to prevent accidental aggregate
+  // initialization which could for example initialize mSuffix as group and
+  // mGroup as origin (if only two string arguments are used).
+  PrincipalMetadata() = default;
+
+  PrincipalMetadata(nsCString aSuffix, nsCString aGroup, nsCString aOrigin)
+      : mSuffix{std::move(aSuffix)},
+        mGroup{std::move(aGroup)},
+        mOrigin{std::move(aOrigin)} {}
+};
+
+struct OriginMetadata : public PrincipalMetadata {
+  PersistenceType mPersistenceType;
+
+  OriginMetadata() = default;
+
+  OriginMetadata(nsCString aSuffix, nsCString aGroup, nsCString aOrigin,
+                 PersistenceType aPersistenceType)
+      : PrincipalMetadata(std::move(aSuffix), std::move(aGroup),
+                          std::move(aOrigin)),
+        mPersistenceType(aPersistenceType) {}
+
+  OriginMetadata(PrincipalMetadata&& aPrincipalMetadata,
+                 PersistenceType aPersistenceType)
+      : PrincipalMetadata(std::move(aPrincipalMetadata)),
+        mPersistenceType(aPersistenceType) {}
+};
+
+struct FullOriginMetadata : OriginMetadata {
+  bool mPersisted;
+  int64_t mLastAccessTime;
+
+  FullOriginMetadata() = default;
+
+  FullOriginMetadata(OriginMetadata aOriginMetadata, bool aPersisted,
+                     int64_t aLastAccessTime)
+      : OriginMetadata(std::move(aOriginMetadata)),
+        mPersisted(aPersisted),
+        mLastAccessTime(aLastAccessTime) {}
+};
+
+struct ClientMetadata : OriginMetadata {
+  const Client::Type mClientType;
+
+  ClientMetadata(OriginMetadata aOriginMetadata, Client::Type aClientType)
+      : OriginMetadata(std::move(aOriginMetadata)), mClientType(aClientType) {}
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_COMMONMETADATA_H_
diff --git a/dom/quota/Config.h b/dom/quota/Config.h
new file mode 100644
index 0000000000..33056265a3
--- /dev/null
+++ b/dom/quota/Config.h
@@ -0,0 +1,32 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_CONFIG_H_
+#define DOM_QUOTA_CONFIG_H_
+
+#ifdef DEBUG
+#  define QM_LOG_ERROR_TO_CONSOLE_ENABLED
+#endif
+
+#define QM_LOG_ERROR_TO_BROWSER_CONSOLE_ENABLED
+
+#if defined(EARLY_BETA_OR_EARLIER) || defined(DEBUG)
+#  define QM_LOG_ERROR_TO_TELEMETRY_ENABLED
+#endif
+
+#if defined(QM_LOG_ERROR_TO_CONSOLE_ENABLED) ||         \
+    defined(QM_LOG_ERROR_TO_BROWSER_CONSOLE_ENABLED) || \
+    defined(QM_LOG_ERROR_TO_TELEMETRY_ENABLED)
+#  define QM_LOG_ERROR_ENABLED
+#endif
+
+#if defined(EARLY_BETA_OR_EARLIER) || defined(DEBUG)
+#  define QM_ERROR_STACKS_ENABLED
+#endif
+
+#define QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+
+#endif  // DOM_QUOTA_CONFIG_H_
diff --git a/dom/quota/DecryptingInputStream.cpp b/dom/quota/DecryptingInputStream.cpp
new file mode 100644
index 0000000000..939b1e3ad7
--- /dev/null
+++ b/dom/quota/DecryptingInputStream.cpp
@@ -0,0 +1,98 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "DecryptingInputStream.h"
+#include "DecryptingInputStream_impl.h"
+
+#include "nsStreamUtils.h"
+
+namespace mozilla::dom::quota {
+
+NS_IMPL_ADDREF(DecryptingInputStreamBase);
+NS_IMPL_RELEASE(DecryptingInputStreamBase);
+
+NS_INTERFACE_MAP_BEGIN(DecryptingInputStreamBase)
+  NS_INTERFACE_MAP_ENTRY(nsIInputStream)
+  NS_INTERFACE_MAP_ENTRY(nsISeekableStream)
+  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsICloneableInputStream,
+                                     mBaseCloneableInputStream || !mBaseStream)
+  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(
+      nsIIPCSerializableInputStream,
+      mBaseIPCSerializableInputStream || !mBaseStream)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIInputStream)
+NS_INTERFACE_MAP_END
+
+DecryptingInputStreamBase::DecryptingInputStreamBase(
+    MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, size_t aBlockSize) {
+  Init(std::move(aBaseStream), aBlockSize);
+}
+
+void DecryptingInputStreamBase::Init(
+    MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, size_t aBlockSize) {
+  mBlockSize.init(aBlockSize);
+  mBaseStream.init(std::move(aBaseStream));
+
+  const nsCOMPtr<nsISeekableStream> seekableStream =
+      do_QueryInterface(mBaseStream->get());
+  MOZ_ASSERT(seekableStream &&
+             SameCOMIdentity(mBaseStream->get(), seekableStream));
+  mBaseSeekableStream.init(WrapNotNullUnchecked(seekableStream));
+
+  const nsCOMPtr<nsICloneableInputStream> cloneableInputStream =
+      do_QueryInterface(mBaseStream->get());
+  if (cloneableInputStream &&
+      SameCOMIdentity(mBaseStream->get(), cloneableInputStream)) {
+    mBaseCloneableInputStream.init(WrapNotNullUnchecked(cloneableInputStream));
+  }
+
+  const nsCOMPtr<nsIIPCSerializableInputStream> ipcSerializeInputStream =
+      do_QueryInterface(mBaseStream->get());
+  if (ipcSerializeInputStream &&
+      SameCOMIdentity(mBaseStream->get(), ipcSerializeInputStream)) {
+    mBaseIPCSerializableInputStream.init(
+        WrapNotNullUnchecked(ipcSerializeInputStream));
+  }
+}
+
+NS_IMETHODIMP DecryptingInputStreamBase::Read(char* aBuf, uint32_t aCount,
+                                              uint32_t* aBytesReadOut) {
+  return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aBytesReadOut);
+}
+
+NS_IMETHODIMP DecryptingInputStreamBase::IsNonBlocking(bool* aNonBlockingOut) {
+  *aNonBlockingOut = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP DecryptingInputStreamBase::SetEOF() {
+  // Cannot truncate a read-only stream.
+
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP DecryptingInputStreamBase::GetCloneable(bool* aCloneable) {
+  *aCloneable = true;
+  return NS_OK;
+}
+
+void DecryptingInputStreamBase::SerializedComplexity(uint32_t aMaxSize,
+                                                     uint32_t* aSizeUsed,
+                                                     uint32_t* aPipes,
+                                                     uint32_t* aTransferables) {
+  (*mBaseIPCSerializableInputStream)
+      ->SerializedComplexity(aMaxSize, aSizeUsed, aPipes, aTransferables);
+}
+
+size_t DecryptingInputStreamBase::PlainLength() const {
+  MOZ_ASSERT(mNextByte <= mPlainBytes);
+  return mPlainBytes - mNextByte;
+}
+
+size_t DecryptingInputStreamBase::EncryptedBufferLength() const {
+  return *mBlockSize;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/DecryptingInputStream.h b/dom/quota/DecryptingInputStream.h
new file mode 100644
index 0000000000..7559ca860e
--- /dev/null
+++ b/dom/quota/DecryptingInputStream.h
@@ -0,0 +1,163 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_DecryptingInputStream_h
+#define mozilla_dom_quota_DecryptingInputStream_h
+
+// Local includes
+#include "EncryptedBlock.h"
+
+// Global includes
+#include <cstddef>
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/NotNull.h"
+#include "mozilla/ipc/InputStreamParams.h"
+#include "nsCOMPtr.h"
+#include "nsICloneableInputStream.h"
+#include "nsIIPCSerializableInputStream.h"
+#include "nsIInputStream.h"
+#include "nsISeekableStream.h"
+#include "nsISupports.h"
+#include "nsITellableStream.h"
+#include "nsTArray.h"
+#include "nscore.h"
+
+template <class T>
+class nsCOMPtr;
+
+namespace mozilla::dom::quota {
+
+class DecryptingInputStreamBase : public nsIInputStream,
+                                  public nsISeekableStream,
+                                  public nsICloneableInputStream,
+                                  public nsIIPCSerializableInputStream {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  NS_IMETHOD Read(char* aBuf, uint32_t aCount, uint32_t* _retval) final;
+  NS_IMETHOD IsNonBlocking(bool* _retval) final;
+
+  NS_IMETHOD SetEOF() final;
+
+  using nsICloneableInputStream::GetCloneable;
+  NS_IMETHOD GetCloneable(bool* aCloneable) final;
+
+  void SerializedComplexity(uint32_t aMaxSize, uint32_t* aSizeUsed,
+                            uint32_t* aPipes,
+                            uint32_t* aTransferables) override;
+
+ protected:
+  DecryptingInputStreamBase(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream,
+                            size_t aBlockSize);
+
+  // For deserialization only.
+  DecryptingInputStreamBase() = default;
+
+  virtual ~DecryptingInputStreamBase() = default;
+
+  void Init(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream,
+            size_t aBlockSize);
+
+  // Convenience routine to determine how many bytes of plain data
+  // we currently have in our buffer.
+  size_t PlainLength() const;
+
+  size_t EncryptedBufferLength() const;
+
+  LazyInitializedOnceEarlyDestructible<const NotNull<nsCOMPtr<nsIInputStream>>>
+      mBaseStream;
+  LazyInitializedOnce<const NotNull<nsISeekableStream*>> mBaseSeekableStream;
+  LazyInitializedOnce<const NotNull<nsICloneableInputStream*>>
+      mBaseCloneableInputStream;
+  LazyInitializedOnce<const NotNull<nsIIPCSerializableInputStream*>>
+      mBaseIPCSerializableInputStream;
+
+  // Number of bytes of plain data in mBuffer.
+  size_t mPlainBytes = 0;
+
+  // Next byte of mBuffer to return in ReadSegments().
+  size_t mNextByte = 0;
+
+  LazyInitializedOnceNotNull<const size_t> mBlockSize;
+
+  size_t mLastBlockLength = 0;
+};
+
+// Wraps another nsIInputStream which contains data written using
+// EncryptingInputStream with a compatible CipherStategy and key. See the
+// remarks on EncryptingOutputStream.
+template <typename CipherStrategy>
+class DecryptingInputStream final : public DecryptingInputStreamBase {
+ public:
+  // Construct a new blocking stream to decrypt the given base stream.  The
+  // base stream must also be blocking.  The base stream does not have to be
+  // buffered.
+  DecryptingInputStream(MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream,
+                        size_t aBlockSize,
+                        typename CipherStrategy::KeyType aKey);
+
+  // For deserialization only.
+  explicit DecryptingInputStream();
+
+  NS_IMETHOD Close() override;
+  NS_IMETHOD Available(uint64_t* _retval) override;
+  NS_IMETHOD ReadSegments(nsWriteSegmentFun aWriter, void* aClosure,
+                          uint32_t aCount, uint32_t* _retval) override;
+
+  NS_DECL_NSITELLABLESTREAM
+
+  NS_IMETHOD Seek(int32_t aWhence, int64_t aOffset) override;
+
+  NS_IMETHOD Clone(nsIInputStream** _retval) override;
+
+  void Serialize(mozilla::ipc::InputStreamParams& aParams, uint32_t aMaxSize,
+                 uint32_t* aSizeUsed) override;
+
+  bool Deserialize(const mozilla::ipc::InputStreamParams& aParams) override;
+
+ private:
+  ~DecryptingInputStream();
+
+  // Parse the next chunk of data.  This may populate mBuffer and set
+  // mBufferFillSize.  This should not be called when mBuffer already
+  // contains data.
+  nsresult ParseNextChunk(uint32_t* aBytesReadOut);
+
+  // Convenience routine to Read() from the base stream until we get
+  // the given number of bytes or reach EOF.
+  //
+  // aBuf           - The buffer to write the bytes into.
+  // aCount         - Max number of bytes to read. If the stream closes
+  //                  fewer bytes my be read.
+  // aMinValidCount - A minimum expected number of bytes.  If we find
+  //                  fewer than this many bytes, then return
+  //                  NS_ERROR_CORRUPTED_CONTENT.  If nothing was read due
+  //                  due to EOF (aBytesReadOut == 0), then NS_OK is returned.
+  // aBytesReadOut  - An out parameter indicating how many bytes were read.
+  nsresult ReadAll(char* aBuf, uint32_t aCount, uint32_t aMinValidCount,
+                   uint32_t* aBytesReadOut);
+
+  bool EnsureBuffers();
+
+  CipherStrategy mCipherStrategy;
+  LazyInitializedOnce<const typename CipherStrategy::KeyType> mKey;
+
+  // Buffer to hold encrypted data.  Must copy here since we need a
+  // flat buffer to run the decryption process on.
+  using EncryptedBlockType = EncryptedBlock<CipherStrategy::BlockPrefixLength,
+                                            CipherStrategy::BasicBlockSize>;
+  Maybe<EncryptedBlockType> mEncryptedBlock;
+
+  // Buffer storing the resulting plain data.
+  nsTArray<uint8_t> mPlainBuffer;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/DecryptingInputStream_impl.h b/dom/quota/DecryptingInputStream_impl.h
new file mode 100644
index 0000000000..ed5353d6ae
--- /dev/null
+++ b/dom/quota/DecryptingInputStream_impl.h
@@ -0,0 +1,520 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_DecryptingInputStream_impl_h
+#define mozilla_dom_quota_DecryptingInputStream_impl_h
+
+#include "DecryptingInputStream.h"
+
+#include <algorithm>
+#include <cstdio>
+#include <type_traits>
+#include <utility>
+#include "CipherStrategy.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/Span.h"
+#include "mozilla/fallible.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsFileStreams.h"
+#include "nsID.h"
+#include "nsIFileStreams.h"
+
+namespace mozilla::dom::quota {
+
+template <typename CipherStrategy>
+DecryptingInputStream<CipherStrategy>::DecryptingInputStream(
+    MovingNotNull<nsCOMPtr<nsIInputStream>> aBaseStream, size_t aBlockSize,
+    typename CipherStrategy::KeyType aKey)
+    : DecryptingInputStreamBase(std::move(aBaseStream), aBlockSize),
+      mKey(aKey) {
+  // XXX Move this to a fallible init function.
+  MOZ_ALWAYS_SUCCEEDS(mCipherStrategy.Init(CipherMode::Decrypt,
+                                           CipherStrategy::SerializeKey(aKey)));
+
+  // This implementation only supports sync base streams.  Verify this in debug
+  // builds.
+#ifdef DEBUG
+  bool baseNonBlocking;
+  nsresult rv = (*mBaseStream)->IsNonBlocking(&baseNonBlocking);
+  MOZ_ASSERT(NS_SUCCEEDED(rv));
+  MOZ_ASSERT(!baseNonBlocking);
+#endif
+}
+
+template <typename CipherStrategy>
+DecryptingInputStream<CipherStrategy>::~DecryptingInputStream() {
+  Close();
+}
+
+template <typename CipherStrategy>
+DecryptingInputStream<CipherStrategy>::DecryptingInputStream()
+    : DecryptingInputStreamBase{} {}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::Close() {
+  if (!mBaseStream) {
+    return NS_OK;
+  }
+
+  (*mBaseStream)->Close();
+  mBaseStream.destroy();
+
+  mPlainBuffer.Clear();
+  mEncryptedBlock.reset();
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::Available(
+    uint64_t* aLengthOut) {
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  int64_t oldPos, endPos;
+  nsresult rv = Tell(&oldPos);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = Seek(SEEK_END, 0);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = Tell(&endPos);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = Seek(SEEK_SET, oldPos);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  *aLengthOut = endPos - oldPos;
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::ReadSegments(
+    nsWriteSegmentFun aWriter, void* aClosure, uint32_t aCount,
+    uint32_t* aBytesReadOut) {
+  *aBytesReadOut = 0;
+
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  nsresult rv;
+
+  // Do not try to use the base stream's ReadSegments here.  Its very
+  // unlikely we will get a single buffer that contains all of the encrypted
+  // data and therefore would have to copy into our own buffer anyways.
+  // Instead, focus on making efficient use of the Read() interface.
+
+  while (aCount > 0) {
+    // We have some decrypted data in our buffer.  Provide it to the callers
+    // writer function.
+    if (mPlainBytes > 0) {
+      MOZ_ASSERT(!mPlainBuffer.IsEmpty());
+      uint32_t remaining = PlainLength();
+      uint32_t numToWrite = std::min(aCount, remaining);
+      uint32_t numWritten;
+      rv = aWriter(this, aClosure,
+                   reinterpret_cast<const char*>(&mPlainBuffer[mNextByte]),
+                   *aBytesReadOut, numToWrite, &numWritten);
+
+      // As defined in nsIInputputStream.idl, do not pass writer func errors.
+      if (NS_FAILED(rv)) {
+        return NS_OK;
+      }
+
+      // End-of-file
+      if (numWritten == 0) {
+        return NS_OK;
+      }
+
+      *aBytesReadOut += numWritten;
+      mNextByte += numWritten;
+      MOZ_ASSERT(mNextByte <= mPlainBytes);
+
+      if (mNextByte == mPlainBytes) {
+        mNextByte = 0;
+        mLastBlockLength = mPlainBytes;
+        mPlainBytes = 0;
+      }
+
+      aCount -= numWritten;
+
+      continue;
+    }
+
+    // Otherwise decrypt the next chunk and loop.  Any resulting data
+    // will set mPlainBytes which we check at the top of the loop.
+    uint32_t bytesRead;
+    rv = ParseNextChunk(&bytesRead);
+    if (NS_FAILED(rv)) {
+      return rv;
+    }
+
+    // If we couldn't read anything and there is no more data to provide
+    // to the caller, then this is eof.
+    if (bytesRead == 0 && mPlainBytes == 0) {
+      return NS_OK;
+    }
+
+    mPlainBytes += bytesRead;
+  }
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+nsresult DecryptingInputStream<CipherStrategy>::ParseNextChunk(
+    uint32_t* const aBytesReadOut) {
+  // There must not be any plain data already in mPlainBuffer.
+  MOZ_ASSERT(mPlainBytes == 0);
+  MOZ_ASSERT(mNextByte == 0);
+
+  *aBytesReadOut = 0;
+
+  if (!EnsureBuffers()) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  // Read the data to our internal encrypted buffer.
+  auto wholeBlock = mEncryptedBlock->MutableWholeBlock();
+  nsresult rv =
+      ReadAll(AsWritableChars(wholeBlock).Elements(), wholeBlock.Length(),
+              wholeBlock.Length(), aBytesReadOut);
+  if (NS_WARN_IF(NS_FAILED(rv)) || *aBytesReadOut == 0) {
+    return rv;
+  }
+
+  // XXX Do we need to know the actual decrypted size?
+  rv = mCipherStrategy.Cipher(mEncryptedBlock->MutableCipherPrefix(),
+                              mEncryptedBlock->Payload(),
+                              AsWritableBytes(Span{mPlainBuffer}));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  *aBytesReadOut = mEncryptedBlock->ActualPayloadLength();
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+nsresult DecryptingInputStream<CipherStrategy>::ReadAll(
+    char* aBuf, uint32_t aCount, uint32_t aMinValidCount,
+    uint32_t* aBytesReadOut) {
+  MOZ_ASSERT(aCount >= aMinValidCount);
+  MOZ_ASSERT(mBaseStream);
+
+  *aBytesReadOut = 0;
+
+  uint32_t offset = 0;
+  while (aCount > 0) {
+    uint32_t bytesRead = 0;
+    nsresult rv = (*mBaseStream)->Read(aBuf + offset, aCount, &bytesRead);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    // EOF, but don't immediately return.  We need to validate min read bytes
+    // below.
+    if (bytesRead == 0) {
+      break;
+    }
+
+    *aBytesReadOut += bytesRead;
+    offset += bytesRead;
+    aCount -= bytesRead;
+  }
+
+  // Reading zero bytes is not an error.  Its the expected EOF condition.
+  // Only compare to the minimum valid count if we read at least one byte.
+  if (*aBytesReadOut != 0 && *aBytesReadOut < aMinValidCount) {
+    return NS_ERROR_CORRUPTED_CONTENT;
+  }
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+bool DecryptingInputStream<CipherStrategy>::EnsureBuffers() {
+  // Lazily create our two buffers so we can report OOM during stream
+  // operation.  These allocations only happens once.  The buffers are reused
+  // until the stream is closed.
+  if (!mEncryptedBlock) {
+    // XXX Do we need to do this fallible (as the comment above suggests)?
+    mEncryptedBlock.emplace(*mBlockSize);
+
+    MOZ_ASSERT(mPlainBuffer.IsEmpty());
+    if (NS_WARN_IF(!mPlainBuffer.SetLength(mEncryptedBlock->MaxPayloadLength(),
+                                           fallible))) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::Tell(
+    int64_t* const aRetval) {
+  MOZ_ASSERT(aRetval);
+
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (!EnsureBuffers()) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  int64_t basePosition;
+  nsresult rv = (*mBaseSeekableStream)->Tell(&basePosition);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  const auto fullBlocks = basePosition / *mBlockSize;
+  MOZ_ASSERT(0 == basePosition % *mBlockSize);
+
+  *aRetval = (fullBlocks - ((mPlainBytes || mLastBlockLength) ? 1 : 0)) *
+                 mEncryptedBlock->MaxPayloadLength() +
+             mNextByte + (mNextByte ? 0 : mLastBlockLength);
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::Seek(const int32_t aWhence,
+                                                          int64_t aOffset) {
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (!EnsureBuffers()) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  int64_t baseBlocksOffset;
+  int64_t nextByteOffset;
+  switch (aWhence) {
+    case NS_SEEK_CUR:
+      // XXX Simplify this without using Tell.
+      {
+        int64_t current;
+        nsresult rv = Tell(&current);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        aOffset += current;
+      }
+      break;
+    case NS_SEEK_SET:
+      break;
+
+    case NS_SEEK_END:
+      // XXX Simplify this without using Seek/Tell.
+      {
+        // XXX The size of the stream could also be queried and stored once
+        // only.
+        nsresult rv = (*mBaseSeekableStream)->Seek(NS_SEEK_SET, 0);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        uint64_t baseStreamSize;
+        rv = (*mBaseStream)->Available(&baseStreamSize);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
+
+        auto decryptedStreamSizeOrErr = [baseStreamSize,
+                                         this]() -> Result<int64_t, nsresult> {
+          if (!baseStreamSize) {
+            return 0;
+          }
+
+          nsresult rv =
+              (*mBaseSeekableStream)
+                  ->Seek(NS_SEEK_END, -static_cast<int64_t>(*mBlockSize));
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return Err(rv);
+          }
+
+          mNextByte = 0;
+          mPlainBytes = 0;
+
+          uint32_t bytesRead;
+          rv = ParseNextChunk(&bytesRead);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return Err(rv);
+          }
+          MOZ_ASSERT(bytesRead);
+
+          // XXX Shouldn't ParseNextChunk better update mPlainBytes?
+          mPlainBytes = bytesRead;
+
+          mNextByte = bytesRead;
+
+          int64_t current;
+          rv = Tell(&current);
+          if (NS_WARN_IF(NS_FAILED(rv))) {
+            return Err(rv);
+          }
+
+          return current;
+        }();
+
+        if (decryptedStreamSizeOrErr.isErr()) {
+          return decryptedStreamSizeOrErr.unwrapErr();
+        }
+
+        aOffset += decryptedStreamSizeOrErr.unwrap();
+      }
+      break;
+
+    default:
+      return NS_ERROR_ILLEGAL_VALUE;
+  }
+
+  baseBlocksOffset = aOffset / mEncryptedBlock->MaxPayloadLength();
+  nextByteOffset = aOffset % mEncryptedBlock->MaxPayloadLength();
+
+  // XXX If we remain in the same block as before, we can skip this.
+  nsresult rv =
+      (*mBaseSeekableStream)->Seek(NS_SEEK_SET, baseBlocksOffset * *mBlockSize);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  mNextByte = 0;
+  mPlainBytes = 0;
+
+  uint32_t readBytes;
+  rv = ParseNextChunk(&readBytes);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    // XXX Do we need to do more here? Restore any previous state?
+    return rv;
+  }
+
+  // We positioned after the last block, we must read that to know its size.
+  // XXX We could know earlier if we positioned us after the last block.
+  if (!readBytes) {
+    if (baseBlocksOffset == 0) {
+      // The stream is empty.
+      return aOffset == 0 ? NS_OK : NS_ERROR_ILLEGAL_VALUE;
+    }
+
+    nsresult rv = (*mBaseSeekableStream)->Seek(NS_SEEK_CUR, -*mBlockSize);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    rv = ParseNextChunk(&readBytes);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      // XXX Do we need to do more here? Restore any previous state?
+      return rv;
+    }
+  }
+
+  mPlainBytes = readBytes;
+  mNextByte = nextByteOffset;
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP DecryptingInputStream<CipherStrategy>::Clone(
+    nsIInputStream** _retval) {
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (!(*mBaseCloneableInputStream)->GetCloneable()) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIInputStream> clonedStream;
+  nsresult rv =
+      (*mBaseCloneableInputStream)->Clone(getter_AddRefs(clonedStream));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  *_retval = MakeAndAddRef<DecryptingInputStream>(
+                 WrapNotNull(std::move(clonedStream)), *mBlockSize, *mKey)
+                 .take();
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+void DecryptingInputStream<CipherStrategy>::Serialize(
+    mozilla::ipc::InputStreamParams& aParams, uint32_t aMaxSize,
+    uint32_t* aSizeUsed) {
+  MOZ_ASSERT(mBaseStream);
+  MOZ_ASSERT(mBaseIPCSerializableInputStream);
+
+  mozilla::ipc::InputStreamParams baseStreamParams;
+  (*mBaseIPCSerializableInputStream)
+      ->Serialize(baseStreamParams, aMaxSize, aSizeUsed);
+
+  MOZ_ASSERT(baseStreamParams.type() ==
+             mozilla::ipc::InputStreamParams::TFileInputStreamParams);
+
+  mozilla::ipc::EncryptedFileInputStreamParams encryptedFileInputStreamParams;
+  encryptedFileInputStreamParams.fileInputStreamParams() =
+      std::move(baseStreamParams);
+  encryptedFileInputStreamParams.key().AppendElements(
+      mCipherStrategy.SerializeKey(*mKey));
+  encryptedFileInputStreamParams.blockSize() = *mBlockSize;
+
+  aParams = std::move(encryptedFileInputStreamParams);
+}
+
+template <typename CipherStrategy>
+bool DecryptingInputStream<CipherStrategy>::Deserialize(
+    const mozilla::ipc::InputStreamParams& aParams) {
+  MOZ_ASSERT(aParams.type() ==
+             mozilla::ipc::InputStreamParams::TEncryptedFileInputStreamParams);
+  const auto& params = aParams.get_EncryptedFileInputStreamParams();
+
+  nsCOMPtr<nsIFileInputStream> stream;
+  nsFileInputStream::Create(NS_GET_IID(nsIFileInputStream),
+                            getter_AddRefs(stream));
+  nsCOMPtr<nsIIPCSerializableInputStream> baseSerializable =
+      do_QueryInterface(stream);
+
+  if (NS_WARN_IF(
+          !baseSerializable->Deserialize(params.fileInputStreamParams()))) {
+    return false;
+  }
+
+  Init(WrapNotNull<nsCOMPtr<nsIInputStream>>(std::move(stream)),
+       params.blockSize());
+  mKey.init(mCipherStrategy.DeserializeKey(params.key()));
+  if (NS_WARN_IF(
+          NS_FAILED(mCipherStrategy.Init(CipherMode::Decrypt, params.key())))) {
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/DirectoryLock.h b/dom/quota/DirectoryLock.h
new file mode 100644
index 0000000000..b35f74b47e
--- /dev/null
+++ b/dom/quota/DirectoryLock.h
@@ -0,0 +1,100 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_DIRECTORYLOCK_H_
+#define DOM_QUOTA_DIRECTORYLOCK_H_
+
+#include "mozilla/dom/Nullable.h"
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+
+namespace mozilla::dom::quota {
+
+class ClientDirectoryLock;
+class OpenDirectoryListener;
+struct OriginMetadata;
+
+// Basic directory lock interface shared by all other directory lock classes.
+// The class must contain pure virtual functions only to avoid problems with
+// multiple inheritance.
+class NS_NO_VTABLE DirectoryLock {
+ public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  virtual int64_t Id() const = 0;
+
+  // XXX This method is now deprecated, use the one which returns the
+  // `BoolPromise`
+  virtual void Acquire(RefPtr<OpenDirectoryListener> aOpenListener) = 0;
+
+  virtual RefPtr<BoolPromise> Acquire() = 0;
+
+  virtual void AcquireImmediately() = 0;
+
+  virtual void AssertIsAcquiredExclusively() = 0;
+
+  virtual void Log() const = 0;
+};
+
+// A directory lock specialized for a given origin directory.
+class NS_NO_VTABLE OriginDirectoryLock : public DirectoryLock {
+ public:
+  // 'Get' prefix is to avoid name collisions with the enum
+  virtual PersistenceType GetPersistenceType() const = 0;
+
+  virtual quota::OriginMetadata OriginMetadata() const = 0;
+
+  virtual const nsACString& Origin() const = 0;
+};
+
+// A directory lock specialized for a given client directory (inside an origin
+// directory).
+class NS_NO_VTABLE ClientDirectoryLock : public OriginDirectoryLock {
+ public:
+  virtual Client::Type ClientType() const = 0;
+};
+
+// A directory lock for universal use. A universal lock can handle any possible
+// combination of nullable persistence type, origin scope and nullable client
+// type.
+//
+// For example, if the persistence type is set to null, origin scope is null
+// and the client type is set to Client::IDB, then the lock will cover
+// <profile>/storage/*/*/idb
+//
+// If no property is set, then the lock will cover the entire storage directory
+// and its subdirectories.
+class UniversalDirectoryLock : public DirectoryLock {
+ public:
+  // XXX Rename to NullablePersistenceTypeRef.
+  virtual const Nullable<PersistenceType>& NullablePersistenceType() const = 0;
+
+  // XXX Rename to OriginScopeRef.
+  virtual const OriginScope& GetOriginScope() const = 0;
+
+  // XXX Rename to NullableClientTypeRef.
+  virtual const Nullable<Client::Type>& NullableClientType() const = 0;
+
+  virtual RefPtr<ClientDirectoryLock> SpecializeForClient(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      Client::Type aClientType) const = 0;
+};
+
+class NS_NO_VTABLE OpenDirectoryListener {
+ public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  virtual void DirectoryLockAcquired(DirectoryLock* aLock) = 0;
+
+  virtual void DirectoryLockFailed() = 0;
+
+ protected:
+  virtual ~OpenDirectoryListener() = default;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_DIRECTORYLOCK_H_
diff --git a/dom/quota/DirectoryLockImpl.cpp b/dom/quota/DirectoryLockImpl.cpp
new file mode 100644
index 0000000000..05c210d195
--- /dev/null
+++ b/dom/quota/DirectoryLockImpl.cpp
@@ -0,0 +1,372 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "DirectoryLockImpl.h"
+
+#include "mozilla/ReverseIterator.h"
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+
+namespace mozilla::dom::quota {
+
+DirectoryLockImpl::DirectoryLockImpl(
+    MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+    const Nullable<PersistenceType>& aPersistenceType,
+    const nsACString& aSuffix, const nsACString& aGroup,
+    const OriginScope& aOriginScope, const Nullable<Client::Type>& aClientType,
+    const bool aExclusive, const bool aInternal,
+    const ShouldUpdateLockIdTableFlag aShouldUpdateLockIdTableFlag)
+    : mQuotaManager(std::move(aQuotaManager)),
+      mPersistenceType(aPersistenceType),
+      mSuffix(aSuffix),
+      mGroup(aGroup),
+      mOriginScope(aOriginScope),
+      mClientType(aClientType),
+      mId(mQuotaManager->GenerateDirectoryLockId()),
+      mExclusive(aExclusive),
+      mInternal(aInternal),
+      mShouldUpdateLockIdTable(aShouldUpdateLockIdTableFlag ==
+                               ShouldUpdateLockIdTableFlag::Yes),
+      mRegistered(false) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT_IF(aOriginScope.IsOrigin(), !aOriginScope.GetOrigin().IsEmpty());
+  MOZ_ASSERT_IF(!aInternal, !aPersistenceType.IsNull());
+  MOZ_ASSERT_IF(!aInternal,
+                aPersistenceType.Value() != PERSISTENCE_TYPE_INVALID);
+  MOZ_ASSERT_IF(!aInternal, !aGroup.IsEmpty());
+  MOZ_ASSERT_IF(!aInternal, aOriginScope.IsOrigin());
+  MOZ_ASSERT_IF(!aInternal, !aClientType.IsNull());
+  MOZ_ASSERT_IF(!aInternal, aClientType.Value() < Client::TypeMax());
+}
+
+DirectoryLockImpl::~DirectoryLockImpl() {
+  AssertIsOnOwningThread();
+
+  // We must call UnregisterDirectoryLock before unblocking other locks because
+  // UnregisterDirectoryLock also updates the origin last access time and the
+  // access flag (if the last lock for given origin is unregistered). One of the
+  // blocked locks could be requested by the clear/reset operation which stores
+  // cached information about origins in storage.sqlite. So if the access flag
+  // is not updated before unblocking the lock for reset/clear, we might store
+  // invalid information which can lead to omitting origin initialization during
+  // next temporary storage initialization.
+  if (mRegistered) {
+    mQuotaManager->UnregisterDirectoryLock(*this);
+  }
+
+  MOZ_ASSERT(!mRegistered);
+
+  for (NotNull<RefPtr<DirectoryLockImpl>> blockingLock : mBlocking) {
+    blockingLock->MaybeUnblock(*this);
+  }
+
+  mBlocking.Clear();
+}
+
+#ifdef DEBUG
+
+void DirectoryLockImpl::AssertIsOnOwningThread() const {
+  mQuotaManager->AssertIsOnOwningThread();
+}
+
+#endif  // DEBUG
+
+bool DirectoryLockImpl::Overlaps(const DirectoryLockImpl& aLock) const {
+  AssertIsOnOwningThread();
+
+  // If the persistence types don't overlap, the op can proceed.
+  if (!aLock.mPersistenceType.IsNull() && !mPersistenceType.IsNull() &&
+      aLock.mPersistenceType.Value() != mPersistenceType.Value()) {
+    return false;
+  }
+
+  // If the origin scopes don't overlap, the op can proceed.
+  bool match = aLock.mOriginScope.Matches(mOriginScope);
+  if (!match) {
+    return false;
+  }
+
+  // If the client types don't overlap, the op can proceed.
+  if (!aLock.mClientType.IsNull() && !mClientType.IsNull() &&
+      aLock.mClientType.Value() != mClientType.Value()) {
+    return false;
+  }
+
+  // Otherwise, when all attributes overlap (persistence type, origin scope and
+  // client type) the op must wait.
+  return true;
+}
+
+bool DirectoryLockImpl::MustWaitFor(const DirectoryLockImpl& aLock) const {
+  AssertIsOnOwningThread();
+
+  // Waiting is never required if the ops in comparison represent shared locks.
+  if (!aLock.mExclusive && !mExclusive) {
+    return false;
+  }
+
+  // Wait if the ops overlap.
+  return Overlaps(aLock);
+}
+
+void DirectoryLockImpl::NotifyOpenListener() {
+  AssertIsOnOwningThread();
+
+  if (mInvalidated) {
+    if (mOpenListener) {
+      (*mOpenListener)->DirectoryLockFailed();
+    } else {
+      mAcquirePromiseHolder.Reject(NS_ERROR_FAILURE, __func__);
+    }
+  } else {
+#ifdef DEBUG
+    mAcquired.Flip();
+#endif
+
+    if (mOpenListener) {
+      (*mOpenListener)
+          ->DirectoryLockAcquired(static_cast<UniversalDirectoryLock*>(this));
+    } else {
+      mAcquirePromiseHolder.Resolve(true, __func__);
+    }
+  }
+
+  if (mOpenListener) {
+    mOpenListener.destroy();
+  } else {
+    MOZ_ASSERT(mAcquirePromiseHolder.IsEmpty());
+  }
+
+  mQuotaManager->RemovePendingDirectoryLock(*this);
+
+  mPending.Flip();
+}
+
+void DirectoryLockImpl::Acquire(RefPtr<OpenDirectoryListener> aOpenListener) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aOpenListener);
+
+  mOpenListener.init(WrapNotNullUnchecked(std::move(aOpenListener)));
+
+  AcquireInternal();
+}
+
+RefPtr<BoolPromise> DirectoryLockImpl::Acquire() {
+  AssertIsOnOwningThread();
+
+  RefPtr<BoolPromise> result = mAcquirePromiseHolder.Ensure(__func__);
+
+  AcquireInternal();
+
+  return result;
+}
+
+void DirectoryLockImpl::AcquireInternal() {
+  AssertIsOnOwningThread();
+
+  mQuotaManager->AddPendingDirectoryLock(*this);
+
+  // See if this lock needs to wait.
+  bool blocked = false;
+
+  // XXX It is probably unnecessary to iterate this in reverse order.
+  for (DirectoryLockImpl* const existingLock :
+       Reversed(mQuotaManager->mDirectoryLocks)) {
+    if (MustWaitFor(*existingLock)) {
+      existingLock->AddBlockingLock(*this);
+      AddBlockedOnLock(*existingLock);
+      blocked = true;
+    }
+  }
+
+  mQuotaManager->RegisterDirectoryLock(*this);
+
+  // Otherwise, notify the open listener immediately.
+  if (!blocked) {
+    NotifyOpenListener();
+    return;
+  }
+
+  if (!mExclusive || !mInternal) {
+    return;
+  }
+
+  // All the locks that block this new exclusive internal lock need to be
+  // invalidated. We also need to notify clients to abort operations for them.
+  QuotaManager::DirectoryLockIdTableArray lockIds;
+  lockIds.SetLength(Client::TypeMax());
+
+  const auto& blockedOnLocks = GetBlockedOnLocks();
+  MOZ_ASSERT(!blockedOnLocks.IsEmpty());
+
+  for (DirectoryLockImpl* blockedOnLock : blockedOnLocks) {
+    if (!blockedOnLock->IsInternal()) {
+      blockedOnLock->Invalidate();
+
+      // Clients don't have to handle pending locks. Invalidation is sufficient
+      // in that case (once a lock is ready and the listener needs to be
+      // notified, we will call DirectoryLockFailed instead of
+      // DirectoryLockAcquired which should release any remaining references to
+      // the lock).
+      if (!blockedOnLock->IsPending()) {
+        lockIds[blockedOnLock->ClientType()].Put(blockedOnLock->Id());
+      }
+    }
+  }
+
+  mQuotaManager->AbortOperationsForLocks(lockIds);
+}
+
+void DirectoryLockImpl::AcquireImmediately() {
+  AssertIsOnOwningThread();
+
+#ifdef DEBUG
+  for (const DirectoryLockImpl* const existingLock :
+       mQuotaManager->mDirectoryLocks) {
+    MOZ_ASSERT(!MustWaitFor(*existingLock));
+  }
+#endif
+
+  mQuotaManager->RegisterDirectoryLock(*this);
+}
+
+#ifdef DEBUG
+void DirectoryLockImpl::AssertIsAcquiredExclusively() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mBlockedOn.IsEmpty());
+  MOZ_ASSERT(mExclusive);
+  MOZ_ASSERT(mInternal);
+  MOZ_ASSERT(mRegistered);
+  MOZ_ASSERT(!mInvalidated);
+  MOZ_ASSERT(mAcquired);
+
+  bool found = false;
+
+  for (const DirectoryLockImpl* const existingLock :
+       mQuotaManager->mDirectoryLocks) {
+    if (existingLock == this) {
+      MOZ_ASSERT(!found);
+      found = true;
+    } else if (existingLock->mAcquired) {
+      MOZ_ASSERT(false);
+    }
+  }
+
+  MOZ_ASSERT(found);
+}
+#endif
+
+RefPtr<ClientDirectoryLock> DirectoryLockImpl::SpecializeForClient(
+    PersistenceType aPersistenceType,
+    const quota::OriginMetadata& aOriginMetadata,
+    Client::Type aClientType) const {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_INVALID);
+  MOZ_ASSERT(!aOriginMetadata.mGroup.IsEmpty());
+  MOZ_ASSERT(!aOriginMetadata.mOrigin.IsEmpty());
+  MOZ_ASSERT(aClientType < Client::TypeMax());
+  MOZ_ASSERT(!mOpenListener);
+  MOZ_ASSERT(mAcquirePromiseHolder.IsEmpty());
+  MOZ_ASSERT(mBlockedOn.IsEmpty());
+
+  if (NS_WARN_IF(mExclusive)) {
+    return nullptr;
+  }
+
+  RefPtr<DirectoryLockImpl> lock = Create(
+      mQuotaManager, Nullable<PersistenceType>(aPersistenceType),
+      aOriginMetadata.mSuffix, aOriginMetadata.mGroup,
+      OriginScope::FromOrigin(aOriginMetadata.mOrigin),
+      Nullable<Client::Type>(aClientType),
+      /* aExclusive */ false, mInternal, ShouldUpdateLockIdTableFlag::Yes);
+  if (NS_WARN_IF(!Overlaps(*lock))) {
+    return nullptr;
+  }
+
+#ifdef DEBUG
+  for (DirectoryLockImpl* const existingLock :
+       Reversed(mQuotaManager->mDirectoryLocks)) {
+    if (existingLock != this && !existingLock->MustWaitFor(*this)) {
+      MOZ_ASSERT(!existingLock->MustWaitFor(*lock));
+    }
+  }
+#endif
+
+  for (const auto& blockedLock : mBlocking) {
+    if (blockedLock->MustWaitFor(*lock)) {
+      lock->AddBlockingLock(*blockedLock);
+      blockedLock->AddBlockedOnLock(*lock);
+    }
+  }
+
+  mQuotaManager->RegisterDirectoryLock(*lock);
+
+  if (mInvalidated) {
+    lock->Invalidate();
+  }
+
+  return lock;
+}
+
+void DirectoryLockImpl::Log() const {
+  AssertIsOnOwningThread();
+
+  if (!QM_LOG_TEST()) {
+    return;
+  }
+
+  QM_LOG(("DirectoryLockImpl [%p]", this));
+
+  nsCString persistenceType;
+  if (mPersistenceType.IsNull()) {
+    persistenceType.AssignLiteral("null");
+  } else {
+    persistenceType.Assign(PersistenceTypeToString(mPersistenceType.Value()));
+  }
+  QM_LOG(("  mPersistenceType: %s", persistenceType.get()));
+
+  QM_LOG(("  mGroup: %s", mGroup.get()));
+
+  nsCString originScope;
+  if (mOriginScope.IsOrigin()) {
+    originScope.AssignLiteral("origin:");
+    originScope.Append(mOriginScope.GetOrigin());
+  } else if (mOriginScope.IsPrefix()) {
+    originScope.AssignLiteral("prefix:");
+    originScope.Append(mOriginScope.GetOriginNoSuffix());
+  } else if (mOriginScope.IsPattern()) {
+    originScope.AssignLiteral("pattern:");
+    // Can't call GetJSONPattern since it only works on the main thread.
+  } else {
+    MOZ_ASSERT(mOriginScope.IsNull());
+    originScope.AssignLiteral("null");
+  }
+  QM_LOG(("  mOriginScope: %s", originScope.get()));
+
+  const auto clientType = mClientType.IsNull()
+                              ? nsAutoCString{"null"_ns}
+                              : Client::TypeToText(mClientType.Value());
+  QM_LOG(("  mClientType: %s", clientType.get()));
+
+  nsCString blockedOnString;
+  for (auto blockedOn : mBlockedOn) {
+    blockedOnString.Append(
+        nsPrintfCString(" [%p]", static_cast<void*>(blockedOn)));
+  }
+  QM_LOG(("  mBlockedOn:%s", blockedOnString.get()));
+
+  QM_LOG(("  mExclusive: %d", mExclusive));
+
+  QM_LOG(("  mInternal: %d", mInternal));
+
+  QM_LOG(("  mInvalidated: %d", static_cast<bool>(mInvalidated)));
+
+  for (auto blockedOn : mBlockedOn) {
+    blockedOn->Log();
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/DirectoryLockImpl.h b/dom/quota/DirectoryLockImpl.h
new file mode 100644
index 0000000000..818d1c81bd
--- /dev/null
+++ b/dom/quota/DirectoryLockImpl.h
@@ -0,0 +1,273 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_DIRECTORYLOCKIMPL_H_
+#define DOM_QUOTA_DIRECTORYLOCKIMPL_H_
+
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/MozPromise.h"
+#include "mozilla/dom/FlippedOnce.h"
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "mozilla/dom/quota/DirectoryLock.h"
+#include "mozilla/dom/quota/OriginScope.h"
+
+namespace mozilla::dom::quota {
+
+enum class ShouldUpdateLockIdTableFlag { No, Yes };
+
+class DirectoryLockImpl final : public ClientDirectoryLock,
+                                public UniversalDirectoryLock {
+  const NotNull<RefPtr<QuotaManager>> mQuotaManager;
+
+  const Nullable<PersistenceType> mPersistenceType;
+  const nsCString mSuffix;
+  const nsCString mGroup;
+  const OriginScope mOriginScope;
+  const Nullable<Client::Type> mClientType;
+  LazyInitializedOnceEarlyDestructible<
+      const NotNull<RefPtr<OpenDirectoryListener>>>
+      mOpenListener;
+  MozPromiseHolder<BoolPromise> mAcquirePromiseHolder;
+
+  nsTArray<NotNull<DirectoryLockImpl*>> mBlocking;
+  nsTArray<NotNull<DirectoryLockImpl*>> mBlockedOn;
+
+  const int64_t mId;
+
+  const bool mExclusive;
+
+  // Internal quota manager operations use this flag to prevent directory lock
+  // registraction/unregistration from updating origin access time, etc.
+  const bool mInternal;
+
+  const bool mShouldUpdateLockIdTable;
+
+  bool mRegistered;
+  FlippedOnce<true> mPending;
+  FlippedOnce<false> mInvalidated;
+
+#ifdef DEBUG
+  FlippedOnce<false> mAcquired;
+#endif
+
+ public:
+  DirectoryLockImpl(MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+                    const Nullable<PersistenceType>& aPersistenceType,
+                    const nsACString& aSuffix, const nsACString& aGroup,
+                    const OriginScope& aOriginScope,
+                    const Nullable<Client::Type>& aClientType, bool aExclusive,
+                    bool aInternal,
+                    ShouldUpdateLockIdTableFlag aShouldUpdateLockIdTableFlag);
+
+  static RefPtr<ClientDirectoryLock> Create(
+      MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+      PersistenceType aPersistenceType,
+      const quota::OriginMetadata& aOriginMetadata, Client::Type aClientType,
+      bool aExclusive) {
+    return Create(std::move(aQuotaManager),
+                  Nullable<PersistenceType>(aPersistenceType),
+                  aOriginMetadata.mSuffix, aOriginMetadata.mGroup,
+                  OriginScope::FromOrigin(aOriginMetadata.mOrigin),
+                  Nullable<Client::Type>(aClientType), aExclusive, false,
+                  ShouldUpdateLockIdTableFlag::Yes);
+  }
+
+  static RefPtr<OriginDirectoryLock> CreateForEviction(
+      MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+      PersistenceType aPersistenceType,
+      const quota::OriginMetadata& aOriginMetadata) {
+    MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_INVALID);
+    MOZ_ASSERT(!aOriginMetadata.mOrigin.IsEmpty());
+
+    return Create(std::move(aQuotaManager),
+                  Nullable<PersistenceType>(aPersistenceType),
+                  aOriginMetadata.mSuffix, aOriginMetadata.mGroup,
+                  OriginScope::FromOrigin(aOriginMetadata.mOrigin),
+                  Nullable<Client::Type>(),
+                  /* aExclusive */ true, /* aInternal */ true,
+                  ShouldUpdateLockIdTableFlag::No);
+  }
+
+  static RefPtr<UniversalDirectoryLock> CreateInternal(
+      MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+      const Nullable<PersistenceType>& aPersistenceType,
+      const OriginScope& aOriginScope,
+      const Nullable<Client::Type>& aClientType, bool aExclusive) {
+    return Create(std::move(aQuotaManager), aPersistenceType, ""_ns, ""_ns,
+                  aOriginScope, aClientType, aExclusive, true,
+                  ShouldUpdateLockIdTableFlag::Yes);
+  }
+
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+  bool IsInternal() const { return mInternal; }
+
+  void SetRegistered(bool aRegistered) { mRegistered = aRegistered; }
+
+  bool IsPending() const { return mPending; }
+
+  // Ideally, we would have just one table (instead of these two:
+  // QuotaManager::mDirectoryLocks and QuotaManager::mDirectoryLockIdTable) for
+  // all registered locks. However, some directory locks need to be accessed off
+  // the PBackground thread, so the access must be protected by the quota mutex.
+  // The problem is that directory locks for eviction must be currently created
+  // while the mutex lock is already acquired. So we decided to have two tables
+  // for now and to not register directory locks for eviction in
+  // QuotaManager::mDirectoryLockIdTable. This can be improved in future after
+  // some refactoring of the mutex locking.
+  bool ShouldUpdateLockIdTable() const { return mShouldUpdateLockIdTable; }
+
+  bool ShouldUpdateLockTable() {
+    return !mInternal &&
+           mPersistenceType.Value() != PERSISTENCE_TYPE_PERSISTENT;
+  }
+
+  bool Overlaps(const DirectoryLockImpl& aLock) const;
+
+  // Test whether this DirectoryLock needs to wait for the given lock.
+  bool MustWaitFor(const DirectoryLockImpl& aLock) const;
+
+  void AddBlockingLock(DirectoryLockImpl& aLock) {
+    AssertIsOnOwningThread();
+
+    mBlocking.AppendElement(WrapNotNull(&aLock));
+  }
+
+  const nsTArray<NotNull<DirectoryLockImpl*>>& GetBlockedOnLocks() {
+    return mBlockedOn;
+  }
+
+  void AddBlockedOnLock(DirectoryLockImpl& aLock) {
+    AssertIsOnOwningThread();
+
+    mBlockedOn.AppendElement(WrapNotNull(&aLock));
+  }
+
+  void MaybeUnblock(DirectoryLockImpl& aLock) {
+    AssertIsOnOwningThread();
+
+    mBlockedOn.RemoveElement(&aLock);
+    if (mBlockedOn.IsEmpty()) {
+      NotifyOpenListener();
+    }
+  }
+
+  void NotifyOpenListener();
+
+  void Invalidate() {
+    AssertIsOnOwningThread();
+
+    mInvalidated.EnsureFlipped();
+  }
+
+  // DirectoryLock interface
+
+  NS_INLINE_DECL_REFCOUNTING(DirectoryLockImpl, override)
+
+  int64_t Id() const override { return mId; }
+
+  void Acquire(RefPtr<OpenDirectoryListener> aOpenListener) override;
+
+  RefPtr<BoolPromise> Acquire() override;
+
+  void AcquireImmediately() override;
+
+  void AssertIsAcquiredExclusively() override
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+  void Log() const override;
+
+  // OriginDirectoryLock interface
+
+  PersistenceType GetPersistenceType() const override {
+    MOZ_DIAGNOSTIC_ASSERT(!mPersistenceType.IsNull());
+
+    return mPersistenceType.Value();
+  }
+
+  quota::OriginMetadata OriginMetadata() const override {
+    MOZ_DIAGNOSTIC_ASSERT(!mGroup.IsEmpty());
+
+    return quota::OriginMetadata{mSuffix, mGroup, nsCString(Origin()),
+                                 GetPersistenceType()};
+  }
+
+  const nsACString& Origin() const override {
+    MOZ_DIAGNOSTIC_ASSERT(mOriginScope.IsOrigin());
+    MOZ_DIAGNOSTIC_ASSERT(!mOriginScope.GetOrigin().IsEmpty());
+
+    return mOriginScope.GetOrigin();
+  }
+
+  // ClientDirectoryLock interface
+
+  Client::Type ClientType() const override {
+    MOZ_DIAGNOSTIC_ASSERT(!mClientType.IsNull());
+    MOZ_DIAGNOSTIC_ASSERT(mClientType.Value() < Client::TypeMax());
+
+    return mClientType.Value();
+  }
+
+  // UniversalDirectoryLock interface
+
+  const Nullable<PersistenceType>& NullablePersistenceType() const override {
+    return mPersistenceType;
+  }
+
+  const OriginScope& GetOriginScope() const override { return mOriginScope; }
+
+  const Nullable<Client::Type>& NullableClientType() const override {
+    return mClientType;
+  }
+
+  RefPtr<ClientDirectoryLock> SpecializeForClient(
+      PersistenceType aPersistenceType,
+      const quota::OriginMetadata& aOriginMetadata,
+      Client::Type aClientType) const override;
+
+ private:
+  ~DirectoryLockImpl();
+
+  static RefPtr<DirectoryLockImpl> Create(
+      MovingNotNull<RefPtr<QuotaManager>> aQuotaManager,
+      const Nullable<PersistenceType>& aPersistenceType,
+      const nsACString& aSuffix, const nsACString& aGroup,
+      const OriginScope& aOriginScope,
+      const Nullable<Client::Type>& aClientType, bool aExclusive,
+      bool aInternal,
+      ShouldUpdateLockIdTableFlag aShouldUpdateLockIdTableFlag) {
+    MOZ_ASSERT_IF(aOriginScope.IsOrigin(), !aOriginScope.GetOrigin().IsEmpty());
+    MOZ_ASSERT_IF(!aInternal, !aPersistenceType.IsNull());
+    MOZ_ASSERT_IF(!aInternal,
+                  aPersistenceType.Value() != PERSISTENCE_TYPE_INVALID);
+    MOZ_ASSERT_IF(!aInternal, !aGroup.IsEmpty());
+    MOZ_ASSERT_IF(!aInternal, aOriginScope.IsOrigin());
+    MOZ_ASSERT_IF(!aInternal, !aClientType.IsNull());
+    MOZ_ASSERT_IF(!aInternal, aClientType.Value() < Client::TypeMax());
+
+    return MakeRefPtr<DirectoryLockImpl>(
+        std::move(aQuotaManager), aPersistenceType, aSuffix, aGroup,
+        aOriginScope, aClientType, aExclusive, aInternal,
+        aShouldUpdateLockIdTableFlag);
+  }
+
+  void AcquireInternal();
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_DIRECTORYLOCKIMPL_H_
diff --git a/dom/quota/DummyCipherStrategy.h b/dom/quota/DummyCipherStrategy.h
new file mode 100644
index 0000000000..6c6b7f7b0d
--- /dev/null
+++ b/dom/quota/DummyCipherStrategy.h
@@ -0,0 +1,56 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_DummyCipherStrategy_h
+#define mozilla_dom_quota_DummyCipherStrategy_h
+
+#include <algorithm>
+#include <array>
+#include <cstddef>
+#include <cstdint>
+#include <utility>
+#include "ErrorList.h"
+#include "mozilla/Result.h"
+#include "mozilla/Span.h"
+#include "mozilla/dom/quota/CipherStrategy.h"
+
+namespace mozilla::dom::quota {
+
+struct DummyCipherStrategy {
+  struct KeyType {};
+
+  static constexpr size_t BlockPrefixLength = 8;
+  static constexpr size_t BasicBlockSize = 4;
+
+  static void DummyTransform(Span<const uint8_t> aIn, Span<uint8_t> aOut) {
+    std::transform(aIn.cbegin(), aIn.cend(), aOut.begin(),
+                   [](const uint8_t byte) { return byte ^ 42; });
+  }
+
+  static Result<KeyType, nsresult> GenerateKey() { return KeyType{}; }
+
+  nsresult Init(CipherMode aCipherMode, Span<const uint8_t> aKey,
+                Span<const uint8_t> aInitialIv = Span<const uint8_t>{}) {
+    return NS_OK;
+  }
+
+  nsresult Cipher(Span<uint8_t> aIv, Span<const uint8_t> aIn,
+                  Span<uint8_t> aOut) {
+    DummyTransform(aIn, aOut);
+    return NS_OK;
+  }
+
+  static std::array<uint8_t, BlockPrefixLength> MakeBlockPrefix() {
+    return {{42, 43, 44, 45}};
+  }
+
+  static Span<const uint8_t> SerializeKey(const KeyType&) { return {}; }
+
+  static KeyType DeserializeKey(const Span<const uint8_t>&) { return {}; }
+};
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/EncryptedBlock.h b/dom/quota/EncryptedBlock.h
new file mode 100644
index 0000000000..703fede8fd
--- /dev/null
+++ b/dom/quota/EncryptedBlock.h
@@ -0,0 +1,93 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_EncryptedBlock_h
+#define mozilla_dom_quota_EncryptedBlock_h
+
+#include <cstdint>
+#include <cstring>
+#include <limits>
+#include "mozilla/Assertions.h"
+#include "mozilla/Span.h"
+#include "nsTArray.h"
+
+namespace mozilla::dom::quota {
+
+// An encrypted block has the following format:
+// - one basic block containing a uint16_t stating the actual payload length
+// - one basic block containing the cipher prefix (tyipically a nonce)
+// - encrypted payload up to the remainder of the specified overall size
+// We currently assume the basic block size is the same as the cipher prefix
+// length.
+//
+// XXX Actually, we don't need the actual payload length in every block. Only
+// the last block may be incomplete. The tricky thing is just that it might be
+// incomplete by just one or two bytes.
+template <size_t CipherPrefixLength, size_t BasicBlockSize>
+class EncryptedBlock {
+ public:
+  explicit EncryptedBlock(const size_t aOverallSize) {
+    MOZ_RELEASE_ASSERT(aOverallSize >
+                       CipherPrefixOffset() + CipherPrefixLength);
+    MOZ_RELEASE_ASSERT(aOverallSize <= std::numeric_limits<uint16_t>::max());
+    // XXX Do we need this to be fallible? Then we need a factory/init function.
+    // But maybe that's not necessary as the block size is not user-provided and
+    // small.
+    mData.SetLength(aOverallSize);
+    SetActualPayloadLength(MaxPayloadLength());
+  }
+
+  size_t MaxPayloadLength() const {
+    return mData.Length() - CipherPrefixLength - CipherPrefixOffset();
+  }
+
+  void SetActualPayloadLength(uint16_t aActualPayloadLength) {
+    memcpy(mData.Elements(), &aActualPayloadLength, sizeof(uint16_t));
+  }
+  size_t ActualPayloadLength() const {
+    return *reinterpret_cast<const uint16_t*>(mData.Elements());
+  }
+
+  using ConstSpan = Span<const uint8_t>;
+  using MutableSpan = Span<uint8_t>;
+
+  ConstSpan CipherPrefix() const {
+    return WholeBlock().Subspan(CipherPrefixOffset(), CipherPrefixLength);
+  }
+  MutableSpan MutableCipherPrefix() {
+    return MutableWholeBlock().Subspan(CipherPrefixOffset(),
+                                       CipherPrefixLength);
+  }
+
+  ConstSpan Payload() const {
+    return WholeBlock()
+        .SplitAt(CipherPrefixOffset() + CipherPrefixLength)
+        .second.First(RoundedUpToBasicBlockSize(ActualPayloadLength()));
+  }
+  MutableSpan MutablePayload() {
+    return MutableWholeBlock()
+        .SplitAt(CipherPrefixOffset() + CipherPrefixLength)
+        .second.First(RoundedUpToBasicBlockSize(ActualPayloadLength()));
+  }
+
+  ConstSpan WholeBlock() const { return mData; }
+  MutableSpan MutableWholeBlock() { return mData; }
+
+ private:
+  static constexpr size_t CipherPrefixOffset() {
+    return RoundedUpToBasicBlockSize(sizeof(uint16_t));
+  }
+
+  static constexpr size_t RoundedUpToBasicBlockSize(const size_t aValue) {
+    return (aValue + BasicBlockSize - 1) / BasicBlockSize * BasicBlockSize;
+  }
+
+  nsTArray<uint8_t> mData;  ///< XXX use some "safe memory" here?
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/EncryptingOutputStream.cpp b/dom/quota/EncryptingOutputStream.cpp
new file mode 100644
index 0000000000..80279eae27
--- /dev/null
+++ b/dom/quota/EncryptingOutputStream.cpp
@@ -0,0 +1,64 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "EncryptingOutputStream.h"
+#include "EncryptingOutputStream_impl.h"
+
+#include <type_traits>
+#include "mozilla/MacroForEach.h"
+#include "nsStreamUtils.h"
+
+namespace mozilla::dom::quota {
+
+NS_IMPL_ISUPPORTS(EncryptingOutputStreamBase, nsIOutputStream);
+
+EncryptingOutputStreamBase::EncryptingOutputStreamBase(
+    nsCOMPtr<nsIOutputStream> aBaseStream, size_t aBlockSize)
+    : mBaseStream(WrapNotNull(std::move(aBaseStream))),
+      mBlockSize(aBlockSize) {}
+
+NS_IMETHODIMP EncryptingOutputStreamBase::Write(const char* aBuf,
+                                                uint32_t aCount,
+                                                uint32_t* aResultOut) {
+  return WriteSegments(NS_CopyBufferToSegment, const_cast<char*>(aBuf), aCount,
+                       aResultOut);
+}
+
+NS_IMETHODIMP EncryptingOutputStreamBase::WriteFrom(nsIInputStream*, uint32_t,
+                                                    uint32_t*) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP EncryptingOutputStreamBase::IsNonBlocking(bool* aNonBlockingOut) {
+  *aNonBlockingOut = false;
+  return NS_OK;
+}
+
+nsresult EncryptingOutputStreamBase::WriteAll(const char* aBuf, uint32_t aCount,
+                                              uint32_t* aBytesWrittenOut) {
+  *aBytesWrittenOut = 0;
+
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  uint32_t offset = 0;
+  while (aCount > 0) {
+    uint32_t numWritten = 0;
+    nsresult rv = (*mBaseStream)->Write(aBuf + offset, aCount, &numWritten);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    offset += numWritten;
+    aCount -= numWritten;
+    *aBytesWrittenOut += numWritten;
+  }
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/EncryptingOutputStream.h b/dom/quota/EncryptingOutputStream.h
new file mode 100644
index 0000000000..adcfe73155
--- /dev/null
+++ b/dom/quota/EncryptingOutputStream.h
@@ -0,0 +1,103 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_EncryptingOutputStream_h
+#define mozilla_dom_quota_EncryptingOutputStream_h
+
+// Local includes
+#include "EncryptedBlock.h"  // for EncryptedBlock
+
+// Global includes
+#include <cstddef>
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/NotNull.h"
+#include "nsCOMPtr.h"
+#include "nsIOutputStream.h"
+#include "nsISupports.h"
+#include "nsTArray.h"
+#include "nscore.h"
+
+class nsIInputStream;
+
+namespace mozilla::dom::quota {
+class EncryptingOutputStreamBase : public nsIOutputStream {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  NS_IMETHOD Write(const char* aBuf, uint32_t aCount, uint32_t* _retval) final;
+  NS_IMETHOD WriteFrom(nsIInputStream* aFromStream, uint32_t aCount,
+                       uint32_t* _retval) final;
+  NS_IMETHOD IsNonBlocking(bool* _retval) final;
+
+ protected:
+  EncryptingOutputStreamBase(nsCOMPtr<nsIOutputStream> aBaseStream,
+                             size_t aBlockSize);
+
+  virtual ~EncryptingOutputStreamBase() = default;
+
+  nsresult WriteAll(const char* aBuf, uint32_t aCount,
+                    uint32_t* aBytesWrittenOut);
+
+  InitializedOnce<const NotNull<nsCOMPtr<nsIOutputStream>>> mBaseStream;
+  const size_t mBlockSize;
+};
+
+// Wraps another nsIOutputStream using the CipherStrategy to encrypt it a
+// page-based manner. Essentially, the CipherStrategy is not actually
+// necessarily doing encryption, but any transformation to a page requiring some
+// fixed-size reserved size per page.
+//
+// Paired with DecryptingInputStream which can be used to read the data written
+// to the underlying stream, using the same (or more generally, a compatible)
+// CipherStrategy, when created with the same key (assuming a symmetric cipher
+// is being used; in principle, an asymmetric cipher would probably also work).
+template <typename CipherStrategy>
+class EncryptingOutputStream final : public EncryptingOutputStreamBase {
+ public:
+  // Construct a new blocking output stream to encrypt data to
+  // the given base stream.  The base stream must also be blocking.
+  // The encryption block size may optionally be set to a value
+  // up to kMaxBlockSize.
+  explicit EncryptingOutputStream(nsCOMPtr<nsIOutputStream> aBaseStream,
+                                  size_t aBlockSize,
+                                  typename CipherStrategy::KeyType aKey);
+
+ private:
+  ~EncryptingOutputStream();
+
+  nsresult FlushToBaseStream();
+
+  bool EnsureBuffers();
+
+  CipherStrategy mCipherStrategy;
+
+  // Buffer holding copied plain data.  This must be copied here
+  // so that the encryption can be performed on a single flat buffer.
+  // XXX This is only necessary if the data written doesn't contain a portion of
+  // effective block size at a block boundary.
+  nsTArray<uint8_t> mBuffer;
+
+  // The next byte in the plain data to copy incoming data to.
+  size_t mNextByte = 0;
+
+  // Buffer holding the resulting encrypted data.
+  using EncryptedBlockType = EncryptedBlock<CipherStrategy::BlockPrefixLength,
+                                            CipherStrategy::BasicBlockSize>;
+  Maybe<EncryptedBlockType> mEncryptedBlock;
+
+ public:
+  NS_IMETHOD Close() override;
+  NS_IMETHOD Flush() override;
+  NS_IMETHOD WriteSegments(nsReadSegmentFun aReader, void* aClosure,
+                           uint32_t aCount, uint32_t* _retval) override;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/EncryptingOutputStream_impl.h b/dom/quota/EncryptingOutputStream_impl.h
new file mode 100644
index 0000000000..25ba7a26a3
--- /dev/null
+++ b/dom/quota/EncryptingOutputStream_impl.h
@@ -0,0 +1,246 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_EncryptingOutputStream_impl_h
+#define mozilla_dom_quota_EncryptingOutputStream_impl_h
+
+#include "EncryptingOutputStream.h"
+
+#include <algorithm>
+#include <utility>
+#include "CipherStrategy.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Span.h"
+#include "mozilla/fallible.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsIAsyncOutputStream.h"
+
+namespace mozilla::dom::quota {
+template <typename CipherStrategy>
+EncryptingOutputStream<CipherStrategy>::EncryptingOutputStream(
+    nsCOMPtr<nsIOutputStream> aBaseStream, size_t aBlockSize,
+    typename CipherStrategy::KeyType aKey)
+    : EncryptingOutputStreamBase(std::move(aBaseStream), aBlockSize) {
+  // XXX Move this to a fallible init function.
+  MOZ_ALWAYS_SUCCEEDS(mCipherStrategy.Init(CipherMode::Encrypt,
+                                           CipherStrategy::SerializeKey(aKey),
+                                           CipherStrategy::MakeBlockPrefix()));
+
+  MOZ_ASSERT(mBlockSize > 0);
+  MOZ_ASSERT(mBlockSize % CipherStrategy::BasicBlockSize == 0);
+  static_assert(
+      CipherStrategy::BlockPrefixLength % CipherStrategy::BasicBlockSize == 0);
+
+  // This implementation only supports sync base streams.  Verify this in debug
+  // builds.  Note, this is a bit complicated because the streams we support
+  // advertise different capabilities:
+  //  - nsFileOutputStream - blocking and sync
+  //  - FixedBufferOutputStream - non-blocking and sync
+  //  - nsPipeOutputStream - can be blocking, but provides async interface
+#ifdef DEBUG
+  bool baseNonBlocking;
+  nsresult rv = (*mBaseStream)->IsNonBlocking(&baseNonBlocking);
+  MOZ_ASSERT(NS_SUCCEEDED(rv));
+  if (baseNonBlocking) {
+    nsCOMPtr<nsIAsyncOutputStream> async =
+        do_QueryInterface((*mBaseStream).get());
+    MOZ_ASSERT(!async);
+  }
+#endif
+}
+
+template <typename CipherStrategy>
+EncryptingOutputStream<CipherStrategy>::~EncryptingOutputStream() {
+  Close();
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP EncryptingOutputStream<CipherStrategy>::Close() {
+  if (!mBaseStream) {
+    return NS_OK;
+  }
+
+  // When closing, flush to the base stream unconditionally, i.e. even if the
+  // buffer is not completely full.
+  nsresult rv = FlushToBaseStream();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // XXX Maybe this Flush call can be removed, since the base stream is closed
+  // afterwards anyway.
+  rv = (*mBaseStream)->Flush();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // XXX What if closing the base stream failed? Fail this method, or at least
+  // log a warning?
+  (*mBaseStream)->Close();
+  mBaseStream.destroy();
+
+  mBuffer.Clear();
+  mEncryptedBlock.reset();
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP EncryptingOutputStream<CipherStrategy>::Flush() {
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (!EnsureBuffers()) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  // We cannot call FlushBaseStream() here if the buffer is not completely
+  // full, we would write an incomplete page, which might be read sequentially,
+  // but we want to support random accesses in DecryptingInputStream, which
+  // would no longer be feasible.
+  if (mNextByte && mNextByte == mEncryptedBlock->MaxPayloadLength()) {
+    nsresult rv = FlushToBaseStream();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+  }
+
+  return (*mBaseStream)->Flush();
+}
+
+template <typename CipherStrategy>
+NS_IMETHODIMP EncryptingOutputStream<CipherStrategy>::WriteSegments(
+    nsReadSegmentFun aReader, void* aClosure, uint32_t aCount,
+    uint32_t* aBytesWrittenOut) {
+  *aBytesWrittenOut = 0;
+
+  if (!mBaseStream) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (!EnsureBuffers()) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  const size_t plainBufferSize = mEncryptedBlock->MaxPayloadLength();
+
+  while (aCount > 0) {
+    // Determine how much space is left in our flat, plain buffer.
+    MOZ_ASSERT(mNextByte <= plainBufferSize);
+    uint32_t remaining = plainBufferSize - mNextByte;
+
+    // If it is full, then encrypt and flush the data to the base stream.
+    if (remaining == 0) {
+      nsresult rv = FlushToBaseStream();
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
+
+      // Now the entire buffer should be available for copying.
+      MOZ_ASSERT(!mNextByte);
+      remaining = plainBufferSize;
+    }
+
+    uint32_t numToRead = std::min(remaining, aCount);
+    uint32_t numRead = 0;
+
+    nsresult rv =
+        aReader(this, aClosure, reinterpret_cast<char*>(&mBuffer[mNextByte]),
+                *aBytesWrittenOut, numToRead, &numRead);
+
+    // As defined in nsIOutputStream.idl, do not pass reader func errors.
+    if (NS_FAILED(rv)) {
+      return NS_OK;
+    }
+
+    // End-of-file
+    if (numRead == 0) {
+      return NS_OK;
+    }
+
+    mNextByte += numRead;
+    *aBytesWrittenOut += numRead;
+    aCount -= numRead;
+  }
+
+  return NS_OK;
+}
+
+template <typename CipherStrategy>
+bool EncryptingOutputStream<CipherStrategy>::EnsureBuffers() {
+  // Lazily create the encrypted buffer on our first flush.  This
+  // allows us to report OOM during stream operation.  This buffer
+  // will then get re-used until the stream is closed.
+  if (!mEncryptedBlock) {
+    // XXX Do we need to do this fallible (as the comment above suggests)?
+    mEncryptedBlock.emplace(mBlockSize);
+    MOZ_ASSERT(mBuffer.IsEmpty());
+
+    if (NS_WARN_IF(!mBuffer.SetLength(mEncryptedBlock->MaxPayloadLength(),
+                                      fallible))) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+template <typename CipherStrategy>
+nsresult EncryptingOutputStream<CipherStrategy>::FlushToBaseStream() {
+  MOZ_ASSERT(mBaseStream);
+
+  if (!mNextByte) {
+    // Nothing to do.
+    return NS_OK;
+  }
+
+  // XXX The compressing stream implementation this was based on wrote a stream
+  // identifier, containing e.g. the block size. Should we do something like
+  // that as well? At the moment, we don't need it, but maybe this were
+  // convenient if we use this for persistent files in the future across version
+  // updates, which might change such parameters.
+
+  const auto iv = mCipherStrategy.MakeBlockPrefix();
+  static_assert(iv.size() * sizeof(decltype(*iv.begin())) ==
+                CipherStrategy::BlockPrefixLength);
+  std::copy(iv.cbegin(), iv.cend(),
+            mEncryptedBlock->MutableCipherPrefix().begin());
+
+  // Encrypt the data to our internal encrypted buffer.
+  // XXX Do we need to know the actual encrypted size?
+  nsresult rv = mCipherStrategy.Cipher(
+      mEncryptedBlock->MutableCipherPrefix(),
+      mozilla::Span(reinterpret_cast<uint8_t*>(mBuffer.Elements()),
+                    ((mNextByte + (CipherStrategy::BasicBlockSize - 1)) /
+                     CipherStrategy::BasicBlockSize) *
+                        CipherStrategy::BasicBlockSize),
+      mEncryptedBlock->MutablePayload());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  mEncryptedBlock->SetActualPayloadLength(mNextByte);
+
+  mNextByte = 0;
+
+  // Write the encrypted buffer out to the base stream.
+  uint32_t numWritten = 0;
+  const auto& wholeBlock = mEncryptedBlock->WholeBlock();
+  rv = WriteAll(AsChars(wholeBlock).Elements(), wholeBlock.Length(),
+                &numWritten);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+  MOZ_ASSERT(wholeBlock.Length() == numWritten);
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/FileStreams.cpp b/dom/quota/FileStreams.cpp
new file mode 100644
index 0000000000..22419fe70c
--- /dev/null
+++ b/dom/quota/FileStreams.cpp
@@ -0,0 +1,200 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "FileStreams.h"
+
+// Local includes
+#include "QuotaCommon.h"
+#include "QuotaManager.h"
+#include "QuotaObject.h"
+#include "RemoteQuotaObject.h"
+
+// Global includes
+#include <utility>
+#include "mozilla/Assertions.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Result.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/ipc/RandomAccessStreamParams.h"
+#include "nsDebug.h"
+#include "prio.h"
+
+namespace mozilla::dom::quota {
+
+template <class FileStreamBase>
+NS_IMETHODIMP FileQuotaStream<FileStreamBase>::SetEOF() {
+  // If the stream is not quota tracked, or on an early or late stage in the
+  // lifecycle, mQuotaObject is null. Under these circumstances,
+  // we don't check the quota limit in order to avoid breakage.
+  if (mQuotaObject) {
+    int64_t offset = 0;
+    QM_TRY(MOZ_TO_RESULT(FileStreamBase::Tell(&offset)));
+
+    QM_TRY(OkIf(mQuotaObject->MaybeUpdateSize(offset, /* aTruncate */ true)),
+           NS_ERROR_FILE_NO_DEVICE_SPACE);
+  }
+
+  QM_TRY(MOZ_TO_RESULT(FileStreamBase::SetEOF()));
+
+  return NS_OK;
+}
+
+template <class FileStreamBase>
+NS_IMETHODIMP FileQuotaStream<FileStreamBase>::Close() {
+  QM_TRY(MOZ_TO_RESULT(FileStreamBase::Close()));
+
+  if (mQuotaObject) {
+    if (auto* remoteQuotaObject = mQuotaObject->AsRemoteQuotaObject()) {
+      remoteQuotaObject->Close();
+    }
+
+    mQuotaObject = nullptr;
+  }
+
+  return NS_OK;
+}
+
+template <class FileStreamBase>
+nsresult FileQuotaStream<FileStreamBase>::DoOpen() {
+  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
+  MOZ_RELEASE_ASSERT(!mDeserialized);
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager, "Shouldn't be null!");
+
+  MOZ_ASSERT(!mQuotaObject, "Creating quota object more than once?");
+  mQuotaObject = quotaManager->GetQuotaObject(
+      mPersistenceType, mOriginMetadata, mClientType,
+      FileStreamBase::mOpenParams.localFile);
+
+  QM_TRY(MOZ_TO_RESULT(FileStreamBase::DoOpen()));
+
+  if (mQuotaObject && (FileStreamBase::mOpenParams.ioFlags & PR_TRUNCATE)) {
+    DebugOnly<bool> res =
+        mQuotaObject->MaybeUpdateSize(0, /* aTruncate */ true);
+    MOZ_ASSERT(res);
+  }
+
+  return NS_OK;
+}
+
+template <class FileStreamBase>
+NS_IMETHODIMP FileQuotaStreamWithWrite<FileStreamBase>::Write(
+    const char* aBuf, uint32_t aCount, uint32_t* _retval) {
+  if (FileQuotaStreamWithWrite::mQuotaObject) {
+    int64_t offset;
+    QM_TRY(MOZ_TO_RESULT(FileStreamBase::Tell(&offset)));
+
+    MOZ_ASSERT(INT64_MAX - offset >= int64_t(aCount));
+
+    if (!FileQuotaStreamWithWrite::mQuotaObject->MaybeUpdateSize(
+            offset + int64_t(aCount),
+            /* aTruncate */ false)) {
+      *_retval = 0;
+      return NS_ERROR_FILE_NO_DEVICE_SPACE;
+    }
+  }
+
+  QM_TRY(MOZ_TO_RESULT(FileStreamBase::Write(aBuf, aCount, _retval)));
+
+  return NS_OK;
+}
+
+mozilla::ipc::RandomAccessStreamParams FileRandomAccessStream::Serialize(
+    nsIInterfaceRequestor* aCallbacks) {
+  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
+  MOZ_RELEASE_ASSERT(!mDeserialized);
+  MOZ_ASSERT(mOpenParams.localFile);
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  RefPtr<QuotaObject> quotaObject = quotaManager->GetQuotaObject(
+      mPersistenceType, mOriginMetadata, mClientType, mOpenParams.localFile);
+  MOZ_ASSERT(quotaObject);
+
+  IPCQuotaObject ipcQuotaObject = quotaObject->Serialize(aCallbacks);
+
+  mozilla::ipc::RandomAccessStreamParams randomAccessStreamParams =
+      nsFileRandomAccessStream::Serialize(aCallbacks);
+
+  MOZ_ASSERT(
+      randomAccessStreamParams.type() ==
+      mozilla::ipc::RandomAccessStreamParams::TFileRandomAccessStreamParams);
+
+  mozilla::ipc::LimitingFileRandomAccessStreamParams
+      limitingFileRandomAccessStreamParams;
+  limitingFileRandomAccessStreamParams.fileRandomAccessStreamParams() =
+      std::move(randomAccessStreamParams);
+  limitingFileRandomAccessStreamParams.quotaObject() =
+      std::move(ipcQuotaObject);
+
+  return limitingFileRandomAccessStreamParams;
+}
+
+bool FileRandomAccessStream::Deserialize(
+    mozilla::ipc::RandomAccessStreamParams& aParams) {
+  MOZ_ASSERT(aParams.type() == mozilla::ipc::RandomAccessStreamParams::
+                                   TLimitingFileRandomAccessStreamParams);
+
+  auto& params = aParams.get_LimitingFileRandomAccessStreamParams();
+
+  mozilla::ipc::RandomAccessStreamParams randomAccessStreamParams(
+      std::move(params.fileRandomAccessStreamParams()));
+
+  QM_TRY(MOZ_TO_RESULT(
+             nsFileRandomAccessStream::Deserialize(randomAccessStreamParams)),
+         false);
+
+  mQuotaObject = QuotaObject::Deserialize(params.quotaObject());
+
+  return true;
+}
+
+Result<MovingNotNull<nsCOMPtr<nsIInputStream>>, nsresult> CreateFileInputStream(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+    Client::Type aClientType, nsIFile* aFile, int32_t aIOFlags, int32_t aPerm,
+    int32_t aBehaviorFlags) {
+  auto stream = MakeRefPtr<FileInputStream>(aPersistenceType, aOriginMetadata,
+                                            aClientType);
+
+  QM_TRY(MOZ_TO_RESULT(stream->Init(aFile, aIOFlags, aPerm, aBehaviorFlags)));
+
+  return WrapMovingNotNullUnchecked(
+      nsCOMPtr<nsIInputStream>(std::move(stream)));
+}
+
+Result<MovingNotNull<nsCOMPtr<nsIOutputStream>>, nsresult>
+CreateFileOutputStream(PersistenceType aPersistenceType,
+                       const OriginMetadata& aOriginMetadata,
+                       Client::Type aClientType, nsIFile* aFile,
+                       int32_t aIOFlags, int32_t aPerm,
+                       int32_t aBehaviorFlags) {
+  auto stream = MakeRefPtr<FileOutputStream>(aPersistenceType, aOriginMetadata,
+                                             aClientType);
+
+  QM_TRY(MOZ_TO_RESULT(stream->Init(aFile, aIOFlags, aPerm, aBehaviorFlags)));
+
+  return WrapMovingNotNullUnchecked(
+      nsCOMPtr<nsIOutputStream>(std::move(stream)));
+}
+
+Result<MovingNotNull<nsCOMPtr<nsIRandomAccessStream>>, nsresult>
+CreateFileRandomAccessStream(PersistenceType aPersistenceType,
+                             const OriginMetadata& aOriginMetadata,
+                             Client::Type aClientType, nsIFile* aFile,
+                             int32_t aIOFlags, int32_t aPerm,
+                             int32_t aBehaviorFlags) {
+  auto stream = MakeRefPtr<FileRandomAccessStream>(
+      aPersistenceType, aOriginMetadata, aClientType);
+
+  QM_TRY(MOZ_TO_RESULT(stream->Init(aFile, aIOFlags, aPerm, aBehaviorFlags)));
+
+  return WrapMovingNotNullUnchecked(
+      nsCOMPtr<nsIRandomAccessStream>(std::move(stream)));
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/FileStreams.h b/dom/quota/FileStreams.h
new file mode 100644
index 0000000000..9a91b474c5
--- /dev/null
+++ b/dom/quota/FileStreams.h
@@ -0,0 +1,176 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_filestreams_h__
+#define mozilla_dom_quota_filestreams_h__
+
+// Local includes
+#include "Client.h"
+
+// Global includes
+#include <cstdint>
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "mozilla/dom/quota/QuotaObject.h"
+#include "nsFileStreams.h"
+#include "nsISupports.h"
+#include "nscore.h"
+
+class nsIFile;
+
+namespace mozilla {
+class Runnable;
+}
+
+namespace mozilla::dom::quota {
+
+class QuotaObject;
+
+template <class FileStreamBase>
+class FileQuotaStream : public FileStreamBase {
+ public:
+  // nsFileStreamBase override
+  NS_IMETHOD
+  SetEOF() override;
+
+  NS_IMETHOD
+  Close() override;
+
+ protected:
+  FileQuotaStream(PersistenceType aPersistenceType,
+                  const OriginMetadata& aOriginMetadata,
+                  Client::Type aClientType)
+      : mPersistenceType(aPersistenceType),
+        mOriginMetadata(aOriginMetadata),
+        mClientType(aClientType),
+        mDeserialized(false) {}
+
+  FileQuotaStream()
+      : mPersistenceType(PERSISTENCE_TYPE_INVALID),
+        mClientType(Client::TYPE_MAX),
+        mDeserialized(true) {}
+
+  ~FileQuotaStream() { Close(); }
+
+  // nsFileStreamBase override
+  virtual nsresult DoOpen() override;
+
+  PersistenceType mPersistenceType;
+  OriginMetadata mOriginMetadata;
+  Client::Type mClientType;
+  RefPtr<QuotaObject> mQuotaObject;
+  const bool mDeserialized;
+};
+
+template <class FileStreamBase>
+class FileQuotaStreamWithWrite : public FileQuotaStream<FileStreamBase> {
+ public:
+  // nsFileStreamBase override
+  NS_IMETHOD
+  Write(const char* aBuf, uint32_t aCount, uint32_t* _retval) override;
+
+ protected:
+  FileQuotaStreamWithWrite(PersistenceType aPersistenceType,
+                           const OriginMetadata& aOriginMetadata,
+                           Client::Type aClientType)
+      : FileQuotaStream<FileStreamBase>(aPersistenceType, aOriginMetadata,
+                                        aClientType) {}
+
+  FileQuotaStreamWithWrite() = default;
+};
+
+class FileInputStream : public FileQuotaStream<nsFileInputStream> {
+ public:
+  NS_INLINE_DECL_REFCOUNTING_INHERITED(FileInputStream,
+                                       FileQuotaStream<nsFileInputStream>)
+
+  FileInputStream(PersistenceType aPersistenceType,
+                  const OriginMetadata& aOriginMetadata,
+                  Client::Type aClientType)
+      : FileQuotaStream<nsFileInputStream>(aPersistenceType, aOriginMetadata,
+                                           aClientType) {}
+
+ private:
+  virtual ~FileInputStream() { Close(); }
+};
+
+class FileOutputStream : public FileQuotaStreamWithWrite<nsFileOutputStream> {
+ public:
+  NS_INLINE_DECL_REFCOUNTING_INHERITED(
+      FileOutputStream, FileQuotaStreamWithWrite<nsFileOutputStream>);
+
+  FileOutputStream(PersistenceType aPersistenceType,
+                   const OriginMetadata& aOriginMetadata,
+                   Client::Type aClientType)
+      : FileQuotaStreamWithWrite<nsFileOutputStream>(
+            aPersistenceType, aOriginMetadata, aClientType) {}
+
+ private:
+  virtual ~FileOutputStream() { Close(); }
+};
+
+// FileRandomAccessStream type is serializable, but only in a restricted
+// manner. The type is only safe to serialize in the parent process and only
+// when the type hasn't been previously deserialized. So the type can be
+// serialized in the parent process and desrialized in a child process or it
+// can be serialized in the parent process and deserialized in the parent
+// process as well (non-e10s mode). The same type can never be
+// serialized/deserialized more than once.
+class FileRandomAccessStream
+    : public FileQuotaStreamWithWrite<nsFileRandomAccessStream> {
+ public:
+  NS_INLINE_DECL_REFCOUNTING_INHERITED(
+      FileRandomAccessStream,
+      FileQuotaStreamWithWrite<nsFileRandomAccessStream>)
+
+  FileRandomAccessStream(PersistenceType aPersistenceType,
+                         const OriginMetadata& aOriginMetadata,
+                         Client::Type aClientType)
+      : FileQuotaStreamWithWrite<nsFileRandomAccessStream>(
+            aPersistenceType, aOriginMetadata, aClientType) {}
+
+  FileRandomAccessStream() = default;
+
+  // nsFileRandomAccessStream override
+
+  // Serialize this FileRandomAccessStream. This method works only in the
+  // parent process and only with streams which haven't been previously
+  // deserialized.
+  mozilla::ipc::RandomAccessStreamParams Serialize(
+      nsIInterfaceRequestor* aCallbacks) override;
+
+  // Deserialize this FileRandomAccessStream. This method works in both the
+  // child and parent.
+  bool Deserialize(mozilla::ipc::RandomAccessStreamParams& aParams) override;
+
+ private:
+  virtual ~FileRandomAccessStream() { Close(); }
+};
+
+Result<MovingNotNull<nsCOMPtr<nsIInputStream>>, nsresult> CreateFileInputStream(
+    PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+    Client::Type aClientType, nsIFile* aFile, int32_t aIOFlags = -1,
+    int32_t aPerm = -1, int32_t aBehaviorFlags = 0);
+
+Result<MovingNotNull<nsCOMPtr<nsIOutputStream>>, nsresult>
+CreateFileOutputStream(PersistenceType aPersistenceType,
+                       const OriginMetadata& aOriginMetadata,
+                       Client::Type aClientType, nsIFile* aFile,
+                       int32_t aIOFlags = -1, int32_t aPerm = -1,
+                       int32_t aBehaviorFlags = 0);
+
+Result<MovingNotNull<nsCOMPtr<nsIRandomAccessStream>>, nsresult>
+CreateFileRandomAccessStream(PersistenceType aPersistenceType,
+                             const OriginMetadata& aOriginMetadata,
+                             Client::Type aClientType, nsIFile* aFile,
+                             int32_t aIOFlags = -1, int32_t aPerm = -1,
+                             int32_t aBehaviorFlags = 0);
+
+}  // namespace mozilla::dom::quota
+
+#endif /* mozilla_dom_quota_filestreams_h__ */
diff --git a/dom/quota/FirstInitializationAttempts.h b/dom/quota/FirstInitializationAttempts.h
new file mode 100644
index 0000000000..e997985371
--- /dev/null
+++ b/dom/quota/FirstInitializationAttempts.h
@@ -0,0 +1,69 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTS_H_
+#define DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTS_H_
+
+#include <cstdint>
+#include <utility>
+#include "ErrorList.h"
+
+namespace mozilla::dom::quota {
+
+template <typename Initialization, typename StringGenerator>
+class FirstInitializationAttempts {
+  Initialization mFirstInitializationAttempts = Initialization::None;
+
+ public:
+  class FirstInitializationAttemptImpl {
+    using FirstInitializationAttemptsType =
+        FirstInitializationAttempts<Initialization, StringGenerator>;
+
+    FirstInitializationAttemptsType& mOwner;
+    const Initialization mInitialization;
+
+   public:
+    FirstInitializationAttemptImpl(FirstInitializationAttemptsType& aOwner,
+                                   const Initialization aInitialization)
+        : mOwner(aOwner), mInitialization(aInitialization) {}
+
+    bool Recorded() const {
+      return mOwner.FirstInitializationAttemptRecorded(mInitialization);
+    }
+
+    void Record(const nsresult aRv) const {
+      mOwner.RecordFirstInitializationAttempt(mInitialization, aRv);
+    }
+  };
+
+  template <typename Func>
+  auto WithFirstInitializationAttempt(const Initialization aInitialization,
+                                      Func&& aFunc)
+      -> std::invoke_result_t<Func, FirstInitializationAttemptImpl&&> {
+    return std::forward<Func>(aFunc)(
+        FirstInitializationAttemptImpl(*this, aInitialization));
+  }
+
+  bool FirstInitializationAttemptRecorded(
+      const Initialization aInitialization) const {
+    return static_cast<bool>(mFirstInitializationAttempts & aInitialization);
+  }
+
+  void RecordFirstInitializationAttempt(const Initialization aInitialization,
+                                        nsresult aRv);
+
+  void ResetFirstInitializationAttempts() {
+    mFirstInitializationAttempts = Initialization::None;
+  }
+};
+
+template <typename Initialization, typename StringGenerator>
+using FirstInitializationAttempt = typename FirstInitializationAttempts<
+    Initialization, StringGenerator>::FirstInitializationAttemptImpl;
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTS_H_
diff --git a/dom/quota/FirstInitializationAttemptsImpl.h b/dom/quota/FirstInitializationAttemptsImpl.h
new file mode 100644
index 0000000000..79ae3daae0
--- /dev/null
+++ b/dom/quota/FirstInitializationAttemptsImpl.h
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTSIMPL_H_
+#define DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTSIMPL_H_
+
+#include "FirstInitializationAttempts.h"
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TelemetryHistogramEnums.h"
+#include "nsError.h"
+
+namespace mozilla::dom::quota {
+
+template <typename Initialization, typename StringGenerator>
+void FirstInitializationAttempts<Initialization, StringGenerator>::
+    RecordFirstInitializationAttempt(const Initialization aInitialization,
+                                     const nsresult aRv) {
+  MOZ_ASSERT(!FirstInitializationAttemptRecorded(aInitialization));
+
+  mFirstInitializationAttempts |= aInitialization;
+
+  if constexpr (!std::is_same_v<StringGenerator, Nothing>) {
+    Telemetry::Accumulate(Telemetry::QM_FIRST_INITIALIZATION_ATTEMPT,
+                          StringGenerator::GetString(aInitialization),
+                          static_cast<uint32_t>(NS_SUCCEEDED(aRv)));
+  }
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_FIRSTINITIALIZATIONATTEMPTSIMPL_H_
diff --git a/dom/quota/Flatten.h b/dom/quota/Flatten.h
new file mode 100644
index 0000000000..2eb29c6010
--- /dev/null
+++ b/dom/quota/Flatten.h
@@ -0,0 +1,118 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_FLATTEN_H_
+#define DOM_QUOTA_FLATTEN_H_
+
+#include <iterator>
+#include <type_traits>
+#include <utility>
+
+// XXX This should be moved to MFBT.
+
+namespace mozilla::dom::quota {
+
+namespace detail {
+
+using std::begin;
+using std::end;
+
+template <typename T, typename NestedRange>
+auto Flatten(NestedRange&& aRange) -> std::enable_if_t<
+    std::is_same_v<T, std::decay_t<typename decltype(begin(
+                          std::declval<const NestedRange&>()))::value_type>>,
+    std::conditional_t<std::is_rvalue_reference_v<NestedRange>,
+                       std::decay_t<NestedRange>, NestedRange>> {
+  return std::forward<NestedRange>(aRange);
+}
+
+template <typename T, typename NestedRange>
+struct FlatIter {
+  using OuterIterator =
+      decltype(begin(std::declval<const std::decay_t<NestedRange>&>()));
+  using InnerIterator =
+      decltype(begin(*begin(std::declval<const std::decay_t<NestedRange>&>())));
+
+  explicit FlatIter(const NestedRange& aRange, OuterIterator aIter)
+      : mOuterIter{std::move(aIter)}, mOuterEnd{end(aRange)} {
+    InitInner();
+  }
+
+  const T& operator*() const { return *mInnerIter; }
+
+  FlatIter& operator++() {
+    ++mInnerIter;
+    if (mInnerIter == mInnerEnd) {
+      ++mOuterIter;
+      InitInner();
+    }
+    return *this;
+  }
+
+  bool operator!=(const FlatIter& aOther) const {
+    return mOuterIter != aOther.mOuterIter ||
+           (mOuterIter != mOuterEnd && mInnerIter != aOther.mInnerIter);
+  }
+
+ private:
+  void InitInner() {
+    while (mOuterIter != mOuterEnd) {
+      const typename OuterIterator::value_type& innerRange = *mOuterIter;
+
+      mInnerIter = begin(innerRange);
+      mInnerEnd = end(innerRange);
+
+      if (mInnerIter != mInnerEnd) {
+        break;
+      }
+
+      ++mOuterIter;
+    }
+  }
+
+  OuterIterator mOuterIter;
+  const OuterIterator mOuterEnd;
+
+  InnerIterator mInnerIter;
+  InnerIterator mInnerEnd;
+};
+
+template <typename T, typename NestedRange>
+struct FlatRange {
+  explicit FlatRange(NestedRange aRange) : mRange{std::move(aRange)} {}
+
+  auto begin() const {
+    using std::begin;
+    return FlatIter<T, NestedRange>{mRange, begin(mRange)};
+  }
+  auto end() const {
+    using std::end;
+    return FlatIter<T, NestedRange>{mRange, end(mRange)};
+  }
+
+ private:
+  NestedRange mRange;
+};
+
+template <typename T, typename NestedRange>
+auto Flatten(NestedRange&& aRange) -> std::enable_if_t<
+    !std::is_same_v<
+        T, std::decay_t<typename decltype(begin(
+               std::declval<const std::decay_t<NestedRange>&>()))::value_type>>,
+    FlatRange<T, NestedRange>> {
+  return FlatRange<T, NestedRange>{std::forward<NestedRange>(aRange)};
+}
+
+}  // namespace detail
+
+template <typename T, typename NestedRange>
+auto Flatten(NestedRange&& aRange) -> decltype(auto) {
+  return detail::Flatten<T>(std::forward<NestedRange>(aRange));
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/ForwardDecls.h b/dom/quota/ForwardDecls.h
new file mode 100644
index 0000000000..6989e91d69
--- /dev/null
+++ b/dom/quota/ForwardDecls.h
@@ -0,0 +1,37 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_FORWARD_DECLS_H_
+#define DOM_QUOTA_FORWARD_DECLS_H_
+
+#include <cstdint>
+#include "mozilla/dom/quota/Config.h"
+
+enum class nsresult : uint32_t;
+
+namespace mozilla {
+
+#ifdef QM_ERROR_STACKS_ENABLED
+class QMResult;
+#else
+using QMResult = nsresult;
+#endif
+
+struct Ok;
+template <typename V, typename E>
+class Result;
+
+using OkOrErr = Result<Ok, QMResult>;
+
+template <typename ResolveValueT, typename RejectValueT, bool IsExclusive>
+class MozPromise;
+
+using BoolPromise = MozPromise<bool, nsresult, false>;
+using Int64Promise = MozPromise<int64_t, nsresult, false>;
+
+}  // namespace mozilla
+
+#endif  // DOM_QUOTA_FORWARD_DECLS_H_
diff --git a/dom/quota/GroupInfo.cpp b/dom/quota/GroupInfo.cpp
new file mode 100644
index 0000000000..96f4f806f6
--- /dev/null
+++ b/dom/quota/GroupInfo.cpp
@@ -0,0 +1,89 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "GroupInfo.h"
+
+#include "mozilla/dom/quota/AssertionsImpl.h"
+#include "OriginInfo.h"
+
+namespace mozilla::dom::quota {
+
+already_AddRefed<OriginInfo> GroupInfo::LockedGetOriginInfo(
+    const nsACString& aOrigin) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  for (const auto& originInfo : mOriginInfos) {
+    if (originInfo->mOrigin == aOrigin) {
+      RefPtr<OriginInfo> result = originInfo;
+      return result.forget();
+    }
+  }
+
+  return nullptr;
+}
+
+void GroupInfo::LockedAddOriginInfo(NotNull<RefPtr<OriginInfo>>&& aOriginInfo) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  NS_ASSERTION(!mOriginInfos.Contains(aOriginInfo),
+               "Replacing an existing entry!");
+  mOriginInfos.AppendElement(std::move(aOriginInfo));
+
+  uint64_t usage = aOriginInfo->LockedUsage();
+
+  if (!aOriginInfo->LockedPersisted()) {
+    AssertNoOverflow(mUsage, usage);
+    mUsage += usage;
+  }
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  AssertNoOverflow(quotaManager->mTemporaryStorageUsage, usage);
+  quotaManager->mTemporaryStorageUsage += usage;
+}
+
+void GroupInfo::LockedAdjustUsageForRemovedOriginInfo(
+    const OriginInfo& aOriginInfo) {
+  const uint64_t usage = aOriginInfo.LockedUsage();
+
+  if (!aOriginInfo.LockedPersisted()) {
+    AssertNoUnderflow(mUsage, usage);
+    mUsage -= usage;
+  }
+
+  QuotaManager* const quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  AssertNoUnderflow(quotaManager->mTemporaryStorageUsage, usage);
+  quotaManager->mTemporaryStorageUsage -= usage;
+}
+
+void GroupInfo::LockedRemoveOriginInfo(const nsACString& aOrigin) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  const auto foundIt = std::find_if(mOriginInfos.cbegin(), mOriginInfos.cend(),
+                                    [&aOrigin](const auto& originInfo) {
+                                      return originInfo->mOrigin == aOrigin;
+                                    });
+
+  // XXX Or can we MOZ_ASSERT(foundIt != mOriginInfos.cend()) ?
+  if (foundIt != mOriginInfos.cend()) {
+    LockedAdjustUsageForRemovedOriginInfo(**foundIt);
+
+    mOriginInfos.RemoveElementAt(foundIt);
+  }
+}
+
+void GroupInfo::LockedRemoveOriginInfos() {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  for (const auto& originInfo : std::exchange(mOriginInfos, {})) {
+    LockedAdjustUsageForRemovedOriginInfo(*originInfo);
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/GroupInfo.h b/dom/quota/GroupInfo.h
new file mode 100644
index 0000000000..a88914743b
--- /dev/null
+++ b/dom/quota/GroupInfo.h
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_GROUPINFO_H_
+#define DOM_QUOTA_GROUPINFO_H_
+
+#include "OriginInfo.h"
+#include "mozilla/NotNull.h"
+#include "mozilla/dom/quota/Assertions.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "nsISupportsImpl.h"
+#include "nsTArray.h"
+
+namespace mozilla::dom::quota {
+
+class GroupInfoPair;
+class OriginInfo;
+
+class GroupInfo final {
+  friend class CanonicalQuotaObject;
+  friend class GroupInfoPair;
+  friend class OriginInfo;
+  friend class QuotaManager;
+
+ public:
+  GroupInfo(GroupInfoPair* aGroupInfoPair, PersistenceType aPersistenceType)
+      : mGroupInfoPair(aGroupInfoPair),
+        mPersistenceType(aPersistenceType),
+        mUsage(0) {
+    MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+    MOZ_COUNT_CTOR(GroupInfo);
+  }
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GroupInfo)
+
+  PersistenceType GetPersistenceType() const { return mPersistenceType; }
+
+ private:
+  // Private destructor, to discourage deletion outside of Release():
+  MOZ_COUNTED_DTOR(GroupInfo)
+
+  already_AddRefed<OriginInfo> LockedGetOriginInfo(const nsACString& aOrigin);
+
+  void LockedAddOriginInfo(NotNull<RefPtr<OriginInfo>>&& aOriginInfo);
+
+  void LockedAdjustUsageForRemovedOriginInfo(const OriginInfo& aOriginInfo);
+
+  void LockedRemoveOriginInfo(const nsACString& aOrigin);
+
+  void LockedRemoveOriginInfos();
+
+  bool LockedHasOriginInfos() {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    return !mOriginInfos.IsEmpty();
+  }
+
+  nsTArray<NotNull<RefPtr<OriginInfo>>> mOriginInfos;
+
+  GroupInfoPair* mGroupInfoPair;
+  PersistenceType mPersistenceType;
+  uint64_t mUsage;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_GROUPINFO_H_
diff --git a/dom/quota/GroupInfoPair.cpp b/dom/quota/GroupInfoPair.cpp
new file mode 100644
index 0000000000..bd912f004b
--- /dev/null
+++ b/dom/quota/GroupInfoPair.cpp
@@ -0,0 +1,26 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "GroupInfoPair.h"
+
+namespace mozilla::dom::quota {
+
+RefPtr<GroupInfo>& GroupInfoPair::GetGroupInfoForPersistenceType(
+    PersistenceType aPersistenceType) {
+  switch (aPersistenceType) {
+    case PERSISTENCE_TYPE_TEMPORARY:
+      return mTemporaryStorageGroupInfo;
+    case PERSISTENCE_TYPE_DEFAULT:
+      return mDefaultStorageGroupInfo;
+
+    case PERSISTENCE_TYPE_PERSISTENT:
+    case PERSISTENCE_TYPE_INVALID:
+    default:
+      MOZ_CRASH("Bad persistence type value!");
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/GroupInfoPair.h b/dom/quota/GroupInfoPair.h
new file mode 100644
index 0000000000..20b8ab8ee9
--- /dev/null
+++ b/dom/quota/GroupInfoPair.h
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_GROUPINFOPAIR_H_
+#define DOM_QUOTA_GROUPINFOPAIR_H_
+
+#include "GroupInfo.h"
+#include "mozilla/dom/quota/Assertions.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "nsISupportsImpl.h"
+#include "nsString.h"
+
+namespace mozilla::dom::quota {
+
+class GroupInfo;
+
+// XXX Consider a new name for this class, it has other data members now
+// (besides two GroupInfo objects).
+class GroupInfoPair {
+ public:
+  GroupInfoPair(const nsACString& aSuffix, const nsACString& aGroup)
+      : mSuffix(aSuffix), mGroup(aGroup) {
+    MOZ_COUNT_CTOR(GroupInfoPair);
+  }
+
+  MOZ_COUNTED_DTOR(GroupInfoPair)
+
+  const nsCString& Suffix() const { return mSuffix; }
+
+  const nsCString& Group() const { return mGroup; }
+
+  RefPtr<GroupInfo> LockedGetGroupInfo(PersistenceType aPersistenceType) {
+    AssertCurrentThreadOwnsQuotaMutex();
+    MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+    return GetGroupInfoForPersistenceType(aPersistenceType);
+  }
+
+  void LockedSetGroupInfo(PersistenceType aPersistenceType,
+                          GroupInfo* aGroupInfo) {
+    AssertCurrentThreadOwnsQuotaMutex();
+    MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+    RefPtr<GroupInfo>& groupInfo =
+        GetGroupInfoForPersistenceType(aPersistenceType);
+    groupInfo = aGroupInfo;
+  }
+
+  void LockedClearGroupInfo(PersistenceType aPersistenceType) {
+    AssertCurrentThreadOwnsQuotaMutex();
+    MOZ_ASSERT(aPersistenceType != PERSISTENCE_TYPE_PERSISTENT);
+
+    RefPtr<GroupInfo>& groupInfo =
+        GetGroupInfoForPersistenceType(aPersistenceType);
+    groupInfo = nullptr;
+  }
+
+  bool LockedHasGroupInfos() {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    return mTemporaryStorageGroupInfo || mDefaultStorageGroupInfo;
+  }
+
+ private:
+  RefPtr<GroupInfo>& GetGroupInfoForPersistenceType(
+      PersistenceType aPersistenceType);
+
+  const nsCString mSuffix;
+  const nsCString mGroup;
+  RefPtr<GroupInfo> mTemporaryStorageGroupInfo;
+  RefPtr<GroupInfo> mDefaultStorageGroupInfo;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_GROUPINFOPAIR_H_
diff --git a/dom/quota/IPCQuotaObject.ipdlh b/dom/quota/IPCQuotaObject.ipdlh
new file mode 100644
index 0000000000..04c86ff585
--- /dev/null
+++ b/dom/quota/IPCQuotaObject.ipdlh
@@ -0,0 +1,20 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PRemoteQuotaObject;
+
+using mozilla::ipc::Endpoint from "mozilla/ipc/Endpoint.h";
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+struct IPCQuotaObject
+{
+  Endpoint<PRemoteQuotaObjectChild> childEndpoint;
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/IPCStreamCipherStrategy.h b/dom/quota/IPCStreamCipherStrategy.h
new file mode 100644
index 0000000000..c66c644827
--- /dev/null
+++ b/dom/quota/IPCStreamCipherStrategy.h
@@ -0,0 +1,16 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_IPCStreamCipherStrategy_h
+#define mozilla_dom_quota_IPCStreamCipherStrategy_h
+
+#include "mozilla/dom/quota/NSSCipherStrategy.h"
+
+namespace mozilla::dom::quota {
+using IPCStreamCipherStrategy = NSSCipherStrategy;
+}
+
+#endif
diff --git a/dom/quota/InitializationTypes.cpp b/dom/quota/InitializationTypes.cpp
new file mode 100644
index 0000000000..fffb4693aa
--- /dev/null
+++ b/dom/quota/InitializationTypes.cpp
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "InitializationTypes.h"
+
+namespace mozilla::dom::quota {
+
+//  static
+nsLiteralCString StringGenerator::GetString(
+    const Initialization aInitialization) {
+  switch (aInitialization) {
+    case Initialization::Storage:
+      return "Storage"_ns;
+    case Initialization::TemporaryStorage:
+      return "TemporaryStorage"_ns;
+    case Initialization::DefaultRepository:
+      return "DefaultRepository"_ns;
+    case Initialization::TemporaryRepository:
+      return "TemporaryRepository"_ns;
+    case Initialization::UpgradeStorageFrom0_0To1_0:
+      return "UpgradeStorageFrom0_0To1_0"_ns;
+    case Initialization::UpgradeStorageFrom1_0To2_0:
+      return "UpgradeStorageFrom1_0To2_0"_ns;
+    case Initialization::UpgradeStorageFrom2_0To2_1:
+      return "UpgradeStorageFrom2_0To2_1"_ns;
+    case Initialization::UpgradeStorageFrom2_1To2_2:
+      return "UpgradeStorageFrom2_1To2_2"_ns;
+    case Initialization::UpgradeStorageFrom2_2To2_3:
+      return "UpgradeStorageFrom2_2To2_3"_ns;
+    case Initialization::UpgradeFromIndexedDBDirectory:
+      return "UpgradeFromIndexedDBDirectory"_ns;
+    case Initialization::UpgradeFromPersistentStorageDirectory:
+      return "UpgradeFromPersistentStorageDirectory"_ns;
+
+    default:
+      MOZ_CRASH("Bad initialization value!");
+  }
+}
+
+// static
+nsLiteralCString StringGenerator::GetString(
+    const OriginInitialization aOriginInitialization) {
+  switch (aOriginInitialization) {
+    case OriginInitialization::PersistentOrigin:
+      return "PersistentOrigin"_ns;
+    case OriginInitialization::TemporaryOrigin:
+      return "TemporaryOrigin"_ns;
+
+    default:
+      MOZ_CRASH("Bad origin initialization value!");
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/InitializationTypes.h b/dom/quota/InitializationTypes.h
new file mode 100644
index 0000000000..06d46abbd1
--- /dev/null
+++ b/dom/quota/InitializationTypes.h
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_INITIALIZATIONTYPES_H_
+#define DOM_QUOTA_INITIALIZATIONTYPES_H_
+
+#include "mozilla/TypedEnumBits.h"
+#include "mozilla/dom/quota/FirstInitializationAttempts.h"
+#include "nsLiteralString.h"
+#include "nsStringFwd.h"
+#include "nsTHashMap.h"
+
+namespace mozilla {
+struct CreateIfNonExistent;
+}
+
+namespace mozilla::dom::quota {
+
+enum class Initialization {
+  None = 0,
+  Storage = 1 << 0,
+  TemporaryStorage = 1 << 1,
+  DefaultRepository = 1 << 2,
+  TemporaryRepository = 1 << 3,
+  UpgradeStorageFrom0_0To1_0 = 1 << 4,
+  UpgradeStorageFrom1_0To2_0 = 1 << 5,
+  UpgradeStorageFrom2_0To2_1 = 1 << 6,
+  UpgradeStorageFrom2_1To2_2 = 1 << 7,
+  UpgradeStorageFrom2_2To2_3 = 1 << 8,
+  UpgradeFromIndexedDBDirectory = 1 << 9,
+  UpgradeFromPersistentStorageDirectory = 1 << 10,
+};
+
+enum class OriginInitialization {
+  None = 0,
+  PersistentOrigin = 1 << 0,
+  TemporaryOrigin = 1 << 1,
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Initialization)
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(OriginInitialization)
+
+class StringGenerator final {
+ public:
+  // TODO: Use constexpr here once bug 1594094 is addressed.
+  static nsLiteralCString GetString(Initialization aInitialization);
+
+  // TODO: Use constexpr here once bug 1594094 is addressed.
+  static nsLiteralCString GetString(OriginInitialization aOriginInitialization);
+};
+
+using OriginInitializationInfo =
+    FirstInitializationAttempts<OriginInitialization, StringGenerator>;
+
+class InitializationInfo
+    : public FirstInitializationAttempts<Initialization, StringGenerator> {
+  nsTHashMap<nsCStringHashKey, OriginInitializationInfo>
+      mOriginInitializationInfos;
+
+ public:
+  OriginInitializationInfo& MutableOriginInitializationInfoRef(
+      const nsACString& aOrigin) {
+    return *mOriginInitializationInfos.Lookup(aOrigin);
+  }
+
+  OriginInitializationInfo& MutableOriginInitializationInfoRef(
+      const nsACString& aOrigin, const CreateIfNonExistent&) {
+    return mOriginInitializationInfos.LookupOrInsert(aOrigin);
+  }
+
+  void ResetOriginInitializationInfos() { mOriginInitializationInfos.Clear(); }
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_INITIALIZATIONTYPES_H_
diff --git a/dom/quota/NSSCipherStrategy.cpp b/dom/quota/NSSCipherStrategy.cpp
new file mode 100644
index 0000000000..d3278b54b7
--- /dev/null
+++ b/dom/quota/NSSCipherStrategy.cpp
@@ -0,0 +1,152 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "NSSCipherStrategy.h"
+
+#include <algorithm>
+#include <cstdlib>
+#include <cstring>
+#include <memory>
+#include <type_traits>
+#include <utility>
+#include "mozilla/Assertions.h"
+#include "mozilla/ResultExtensions.h"
+
+// NSS includes
+#include "blapit.h"
+#include "pk11pub.h"
+#include "pkcs11t.h"
+#include "seccomon.h"
+#include "secmodt.h"
+
+namespace mozilla::dom::quota {
+
+static_assert(sizeof(NSSCipherStrategy::KeyType) == 32);
+static_assert(NSSCipherStrategy::BlockPrefixLength == 32);
+static_assert(NSSCipherStrategy::BasicBlockSize == 16);
+
+Result<NSSCipherStrategy::KeyType, nsresult> NSSCipherStrategy::GenerateKey() {
+  const auto slot = UniquePK11SlotInfo{PK11_GetInternalSlot()};
+  if (slot == nullptr) {
+    return Err(NS_ERROR_FAILURE);
+  }
+  const auto symKey = UniquePK11SymKey{PK11_KeyGen(
+      slot.get(), CKM_CHACHA20_KEY_GEN, nullptr, sizeof(KeyType), nullptr)};
+  if (symKey == nullptr) {
+    return Err(NS_ERROR_FAILURE);
+  }
+  if (PK11_ExtractKeyValue(symKey.get()) != SECSuccess) {
+    return Err(NS_ERROR_FAILURE);
+  }
+  // No need to free keyData as it is a buffer managed by symKey.
+  SECItem* keyData = PK11_GetKeyData(symKey.get());
+  if (keyData == nullptr) {
+    return Err(NS_ERROR_FAILURE);
+  }
+  KeyType key;
+  MOZ_RELEASE_ASSERT(keyData->len == key.size());
+  std::copy(keyData->data, keyData->data + key.size(), key.data());
+  return key;
+}
+
+nsresult NSSCipherStrategy::Init(const CipherMode aMode,
+                                 const Span<const uint8_t> aKey,
+                                 const Span<const uint8_t> aInitialIv) {
+  MOZ_ASSERT_IF(CipherMode::Encrypt == aMode, aInitialIv.Length() == 32);
+
+  mMode.init(aMode);
+
+  mIv.AppendElements(aInitialIv);
+
+  const auto slot = UniquePK11SlotInfo{PK11_GetInternalSlot()};
+  if (slot == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  SECItem keyItem;
+  keyItem.data = const_cast<uint8_t*>(aKey.Elements());
+  keyItem.len = aKey.Length();
+  const auto symKey = UniquePK11SymKey{
+      PK11_ImportSymKey(slot.get(), CKM_CHACHA20_POLY1305, PK11_OriginUnwrap,
+                        CKA_ENCRYPT, &keyItem, nullptr)};
+  if (symKey == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  SECItem empty = {siBuffer, nullptr, 0};
+  auto pk11Context = UniquePK11Context{PK11_CreateContextBySymKey(
+      CKM_CHACHA20_POLY1305,
+      CKA_NSS_MESSAGE |
+          (CipherMode::Encrypt == aMode ? CKA_ENCRYPT : CKA_DECRYPT),
+      symKey.get(), &empty)};
+  if (pk11Context == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  mPK11Context.init(std::move(pk11Context));
+  return NS_OK;
+}
+
+nsresult NSSCipherStrategy::Cipher(const Span<uint8_t> aIv,
+                                   const Span<const uint8_t> aIn,
+                                   const Span<uint8_t> aOut) {
+  if (CipherMode::Encrypt == *mMode) {
+    MOZ_RELEASE_ASSERT(aIv.Length() == mIv.Length());
+    memcpy(aIv.Elements(), mIv.Elements(), aIv.Length());
+  }
+
+  // XXX make tag a separate parameter
+  constexpr size_t tagLen = 16;
+  const auto tag = Span{aIv}.Last(tagLen);
+  // tag is const on decrypt, but returned on encrypt
+
+  const auto iv = Span{aIv}.First(12);
+  MOZ_ASSERT(tag.Length() + iv.Length() <= aIv.Length());
+
+  int outLen;
+  // aIn and aOut may not overlap resp. be the same, so we can't do this
+  // in-place.
+  const SECStatus rv = PK11_AEADOp(
+      mPK11Context->get(), CKG_GENERATE_COUNTER, 0, iv.Elements(), iv.Length(),
+      nullptr, 0, aOut.Elements(), &outLen, aOut.Length(), tag.Elements(),
+      tag.Length(), aIn.Elements(), aIn.Length());
+
+  if (CipherMode::Encrypt == *mMode) {
+    memcpy(mIv.Elements(), aIv.Elements(), aIv.Length());
+  }
+
+  return MapSECStatus(rv);
+}
+
+template <size_t N>
+static std::array<uint8_t, N> MakeRandomData() {
+  std::array<uint8_t, N> res;
+
+  const auto rv = PK11_GenerateRandom(res.data(), res.size());
+  /// XXX Allow return of error code to handle this gracefully.
+  MOZ_RELEASE_ASSERT(rv == SECSuccess);
+
+  return res;
+}
+
+std::array<uint8_t, NSSCipherStrategy::BlockPrefixLength>
+NSSCipherStrategy::MakeBlockPrefix() {
+  return MakeRandomData<BlockPrefixLength>();
+}
+
+Span<const uint8_t> NSSCipherStrategy::SerializeKey(const KeyType& aKey) {
+  return Span(aKey);
+}
+
+NSSCipherStrategy::KeyType NSSCipherStrategy::DeserializeKey(
+    const Span<const uint8_t>& aSerializedKey) {
+  KeyType res;
+  MOZ_ASSERT(res.size() == aSerializedKey.size());
+  std::copy(aSerializedKey.cbegin(), aSerializedKey.cend(), res.begin());
+  return res;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/NSSCipherStrategy.h b/dom/quota/NSSCipherStrategy.h
new file mode 100644
index 0000000000..31b3eb03e2
--- /dev/null
+++ b/dom/quota/NSSCipherStrategy.h
@@ -0,0 +1,56 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_NSSCipherStrategy_h
+#define mozilla_dom_quota_NSSCipherStrategy_h
+
+#include "CipherStrategy.h"
+
+#include <cstddef>
+#include <cstdint>
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/Result.h"
+#include "mozilla/Span.h"
+#include "ErrorList.h"
+#include "nsTArray.h"
+
+#include "ScopedNSSTypes.h"
+
+#include <array>
+
+namespace mozilla::dom::quota {
+
+struct NSSCipherStrategy {
+  // Use numeric literals here to avoid having to include NSS headers here.
+  // static_assert's in the cpp file check their consistency.
+  using KeyType = std::array<uint8_t, 32>;
+  static constexpr size_t BlockPrefixLength = 32;
+  static constexpr size_t BasicBlockSize = 16;
+
+  static Result<KeyType, nsresult> GenerateKey();
+
+  nsresult Init(CipherMode aCipherMode, Span<const uint8_t> aKey,
+                Span<const uint8_t> aInitialIv = Span<const uint8_t>{});
+
+  nsresult Cipher(Span<uint8_t> aIv, Span<const uint8_t> aIn,
+                  Span<uint8_t> aOut);
+
+  static std::array<uint8_t, BlockPrefixLength> MakeBlockPrefix();
+
+  static Span<const uint8_t> SerializeKey(const KeyType& aKey);
+
+  static KeyType DeserializeKey(const Span<const uint8_t>& aSerializedKey);
+
+ private:
+  // XXX Remove EarlyDestructible, remove moving of the CipherStrategy.
+  LazyInitializedOnceEarlyDestructible<const CipherMode> mMode;
+  LazyInitializedOnceEarlyDestructible<const UniquePK11Context> mPK11Context;
+  nsTArray<uint8_t> mIv;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif
diff --git a/dom/quota/OriginInfo.cpp b/dom/quota/OriginInfo.cpp
new file mode 100644
index 0000000000..4985bb627c
--- /dev/null
+++ b/dom/quota/OriginInfo.cpp
@@ -0,0 +1,167 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "OriginInfo.h"
+
+#include "GroupInfo.h"
+#include "GroupInfoPair.h"
+#include "mozilla/dom/quota/AssertionsImpl.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/dom/quota/UsageInfo.h"
+
+namespace mozilla::dom::quota {
+
+OriginInfo::OriginInfo(GroupInfo* aGroupInfo, const nsACString& aOrigin,
+                       const ClientUsageArray& aClientUsages, uint64_t aUsage,
+                       int64_t aAccessTime, bool aPersisted,
+                       bool aDirectoryExists)
+    : mClientUsages(aClientUsages.Clone()),
+      mGroupInfo(aGroupInfo),
+      mOrigin(aOrigin),
+      mUsage(aUsage),
+      mAccessTime(aAccessTime),
+      mAccessed(false),
+      mPersisted(aPersisted),
+      mDirectoryExists(aDirectoryExists) {
+  MOZ_ASSERT(aGroupInfo);
+  MOZ_ASSERT(aClientUsages.Length() == Client::TypeMax());
+  MOZ_ASSERT_IF(aPersisted,
+                aGroupInfo->mPersistenceType == PERSISTENCE_TYPE_DEFAULT);
+
+  // This constructor is called from the "QuotaManager IO" thread and so
+  // we can't check if the principal has a WebExtensionPolicy instance
+  // associated to it, and even besides that if the extension is currently
+  // disabled (and so no WebExtensionPolicy instance would actually exist)
+  // its stored data shouldn't be cleared until the extension is uninstalled
+  // and so here we resort to check the origin scheme instead.
+  mIsExtension = StringBeginsWith(mOrigin, "moz-extension://"_ns);
+
+#ifdef DEBUG
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  uint64_t usage = 0;
+  for (Client::Type type : quotaManager->AllClientTypes()) {
+    AssertNoOverflow(usage, aClientUsages[type].valueOr(0));
+    usage += aClientUsages[type].valueOr(0);
+  }
+  MOZ_ASSERT(aUsage == usage);
+#endif
+
+  MOZ_COUNT_CTOR(OriginInfo);
+}
+
+OriginMetadata OriginInfo::FlattenToOriginMetadata() const {
+  return {mGroupInfo->mGroupInfoPair->Suffix(),
+          mGroupInfo->mGroupInfoPair->Group(), mOrigin,
+          mGroupInfo->mPersistenceType};
+}
+
+FullOriginMetadata OriginInfo::LockedFlattenToFullOriginMetadata() const {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  return {FlattenToOriginMetadata(), mPersisted, mAccessTime};
+}
+
+nsresult OriginInfo::LockedBindToStatement(
+    mozIStorageStatement* aStatement) const {
+  AssertCurrentThreadOwnsQuotaMutex();
+  MOZ_ASSERT(mGroupInfo);
+
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindInt32ByName(
+      "repository_id"_ns, mGroupInfo->mPersistenceType)));
+
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindUTF8StringByName(
+      "suffix"_ns, mGroupInfo->mGroupInfoPair->Suffix())));
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindUTF8StringByName(
+      "group_"_ns, mGroupInfo->mGroupInfoPair->Group())));
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindUTF8StringByName("origin"_ns, mOrigin)));
+
+  nsCString clientUsagesText;
+  mClientUsages.Serialize(clientUsagesText);
+
+  QM_TRY(MOZ_TO_RESULT(
+      aStatement->BindUTF8StringByName("client_usages"_ns, clientUsagesText)));
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindInt64ByName("usage"_ns, mUsage)));
+  QM_TRY(MOZ_TO_RESULT(
+      aStatement->BindInt64ByName("last_access_time"_ns, mAccessTime)));
+  QM_TRY(MOZ_TO_RESULT(aStatement->BindInt32ByName("accessed"_ns, mAccessed)));
+  QM_TRY(
+      MOZ_TO_RESULT(aStatement->BindInt32ByName("persisted"_ns, mPersisted)));
+
+  return NS_OK;
+}
+
+void OriginInfo::LockedDecreaseUsage(Client::Type aClientType, int64_t aSize) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  MOZ_ASSERT(mClientUsages[aClientType].isSome());
+  AssertNoUnderflow(mClientUsages[aClientType].value(), aSize);
+  mClientUsages[aClientType] = Some(mClientUsages[aClientType].value() - aSize);
+
+  AssertNoUnderflow(mUsage, aSize);
+  mUsage -= aSize;
+
+  if (!LockedPersisted()) {
+    AssertNoUnderflow(mGroupInfo->mUsage, aSize);
+    mGroupInfo->mUsage -= aSize;
+  }
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  AssertNoUnderflow(quotaManager->mTemporaryStorageUsage, aSize);
+  quotaManager->mTemporaryStorageUsage -= aSize;
+}
+
+void OriginInfo::LockedResetUsageForClient(Client::Type aClientType) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  uint64_t size = mClientUsages[aClientType].valueOr(0);
+
+  mClientUsages[aClientType].reset();
+
+  AssertNoUnderflow(mUsage, size);
+  mUsage -= size;
+
+  if (!LockedPersisted()) {
+    AssertNoUnderflow(mGroupInfo->mUsage, size);
+    mGroupInfo->mUsage -= size;
+  }
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  MOZ_ASSERT(quotaManager);
+
+  AssertNoUnderflow(quotaManager->mTemporaryStorageUsage, size);
+  quotaManager->mTemporaryStorageUsage -= size;
+}
+
+UsageInfo OriginInfo::LockedGetUsageForClient(Client::Type aClientType) {
+  AssertCurrentThreadOwnsQuotaMutex();
+
+  // The current implementation of this method only supports DOMCACHE and LS,
+  // which only use DatabaseUsage. If this assertion is lifted, the logic below
+  // must be adapted.
+  MOZ_ASSERT(aClientType == Client::Type::DOMCACHE ||
+             aClientType == Client::Type::LS ||
+             aClientType == Client::Type::FILESYSTEM);
+
+  return UsageInfo{DatabaseUsageType{mClientUsages[aClientType]}};
+}
+
+void OriginInfo::LockedPersist() {
+  AssertCurrentThreadOwnsQuotaMutex();
+  MOZ_ASSERT(mGroupInfo->mPersistenceType == PERSISTENCE_TYPE_DEFAULT);
+  MOZ_ASSERT(!mPersisted);
+
+  mPersisted = true;
+
+  // Remove Usage from GroupInfo
+  AssertNoUnderflow(mGroupInfo->mUsage, mUsage);
+  mGroupInfo->mUsage -= mUsage;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/OriginInfo.h b/dom/quota/OriginInfo.h
new file mode 100644
index 0000000000..33a3a30355
--- /dev/null
+++ b/dom/quota/OriginInfo.h
@@ -0,0 +1,138 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_ORIGININFO_H_
+#define DOM_QUOTA_ORIGININFO_H_
+
+#include "Assertions.h"
+#include "ClientUsageArray.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+
+namespace mozilla::dom::quota {
+
+class CanonicalQuotaObject;
+class GroupInfo;
+
+class OriginInfo final {
+  friend class CanonicalQuotaObject;
+  friend class GroupInfo;
+  friend class QuotaManager;
+
+ public:
+  OriginInfo(GroupInfo* aGroupInfo, const nsACString& aOrigin,
+             const ClientUsageArray& aClientUsages, uint64_t aUsage,
+             int64_t aAccessTime, bool aPersisted, bool aDirectoryExists);
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(OriginInfo)
+
+  GroupInfo* GetGroupInfo() const { return mGroupInfo; }
+
+  const nsCString& Origin() const { return mOrigin; }
+
+  int64_t LockedUsage() const {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+#ifdef DEBUG
+    QuotaManager* quotaManager = QuotaManager::Get();
+    MOZ_ASSERT(quotaManager);
+
+    uint64_t usage = 0;
+    for (Client::Type type : quotaManager->AllClientTypes()) {
+      AssertNoOverflow(usage, mClientUsages[type].valueOr(0));
+      usage += mClientUsages[type].valueOr(0);
+    }
+    MOZ_ASSERT(mUsage == usage);
+#endif
+
+    return mUsage;
+  }
+
+  int64_t LockedAccessTime() const {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    return mAccessTime;
+  }
+
+  bool LockedPersisted() const {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    return mPersisted;
+  }
+
+  OriginMetadata FlattenToOriginMetadata() const;
+
+  FullOriginMetadata LockedFlattenToFullOriginMetadata() const;
+
+  nsresult LockedBindToStatement(mozIStorageStatement* aStatement) const;
+
+ private:
+  // Private destructor, to discourage deletion outside of Release():
+  ~OriginInfo() {
+    MOZ_COUNT_DTOR(OriginInfo);
+
+    MOZ_ASSERT(!mCanonicalQuotaObjects.Count());
+  }
+
+  void LockedDecreaseUsage(Client::Type aClientType, int64_t aSize);
+
+  void LockedResetUsageForClient(Client::Type aClientType);
+
+  UsageInfo LockedGetUsageForClient(Client::Type aClientType);
+
+  void LockedUpdateAccessTime(int64_t aAccessTime) {
+    AssertCurrentThreadOwnsQuotaMutex();
+
+    mAccessTime = aAccessTime;
+    if (!mAccessed) {
+      mAccessed = true;
+    }
+  }
+
+  void LockedPersist();
+
+  bool IsExtensionOrigin() { return mIsExtension; }
+
+  nsTHashMap<nsStringHashKey, NotNull<CanonicalQuotaObject*>>
+      mCanonicalQuotaObjects;
+  ClientUsageArray mClientUsages;
+  GroupInfo* mGroupInfo;
+  const nsCString mOrigin;
+  bool mIsExtension;
+  uint64_t mUsage;
+  int64_t mAccessTime;
+  bool mAccessed;
+  bool mPersisted;
+  /**
+   * In some special cases like the LocalStorage client where it's possible to
+   * create a Quota-using representation but not actually write any data, we
+   * want to be able to track quota for an origin without creating its origin
+   * directory or the per-client files until they are actually needed to store
+   * data. In those cases, the OriginInfo will be created by
+   * EnsureQuotaForOrigin and the resulting mDirectoryExists will be false until
+   * the origin actually needs to be created. It is possible for mUsage to be
+   * greater than zero while mDirectoryExists is false, representing a state
+   * where a client like LocalStorage has reserved quota for disk writes, but
+   * has not yet flushed the data to disk.
+   */
+  bool mDirectoryExists;
+};
+
+class OriginInfoAccessTimeComparator {
+ public:
+  bool Equals(const NotNull<RefPtr<const OriginInfo>>& a,
+              const NotNull<RefPtr<const OriginInfo>>& b) const {
+    return a->LockedAccessTime() == b->LockedAccessTime();
+  }
+
+  bool LessThan(const NotNull<RefPtr<const OriginInfo>>& a,
+                const NotNull<RefPtr<const OriginInfo>>& b) const {
+    return a->LockedAccessTime() < b->LockedAccessTime();
+  }
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_ORIGININFO_H_
diff --git a/dom/quota/OriginScope.h b/dom/quota/OriginScope.h
new file mode 100644
index 0000000000..a7047e5c82
--- /dev/null
+++ b/dom/quota/OriginScope.h
@@ -0,0 +1,344 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_originorpatternstring_h__
+#define mozilla_dom_quota_originorpatternstring_h__
+
+#include <utility>
+#include "mozilla/Assertions.h"
+#include "mozilla/OriginAttributes.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Variant.h"
+#include "nsStringFlags.h"
+#include "nsStringFwd.h"
+
+namespace mozilla::dom::quota {
+
+class OriginScope {
+  class Origin {
+    nsCString mOrigin;
+    nsCString mOriginNoSuffix;
+    UniquePtr<OriginAttributes> mAttributes;
+
+   public:
+    explicit Origin(const nsACString& aOrigin) : mOrigin(aOrigin) {
+      InitMembers();
+    }
+
+    Origin(const Origin& aOther)
+        : mOrigin(aOther.mOrigin),
+          mOriginNoSuffix(aOther.mOriginNoSuffix),
+          mAttributes(MakeUnique<OriginAttributes>(*aOther.mAttributes)) {}
+
+    Origin(Origin&& aOther) = default;
+
+    const nsACString& GetOrigin() const { return mOrigin; }
+
+    void SetOrigin(const nsACString& aOrigin) {
+      mOrigin = aOrigin;
+
+      InitMembers();
+    }
+
+    const nsACString& GetOriginNoSuffix() const { return mOriginNoSuffix; }
+
+    const OriginAttributes& GetAttributes() const {
+      MOZ_ASSERT(mAttributes);
+
+      return *mAttributes;
+    }
+
+   private:
+    void InitMembers() {
+      mAttributes = MakeUnique<OriginAttributes>();
+
+      MOZ_ALWAYS_TRUE(
+          mAttributes->PopulateFromOrigin(mOrigin, mOriginNoSuffix));
+    }
+  };
+
+  class Prefix {
+    nsCString mOriginNoSuffix;
+
+   public:
+    explicit Prefix(const nsACString& aOriginNoSuffix)
+        : mOriginNoSuffix(aOriginNoSuffix) {}
+
+    const nsCString& GetOriginNoSuffix() const { return mOriginNoSuffix; }
+
+    void SetOriginNoSuffix(const nsACString& aOriginNoSuffix) {
+      mOriginNoSuffix = aOriginNoSuffix;
+    }
+  };
+
+  class Pattern {
+    UniquePtr<OriginAttributesPattern> mPattern;
+
+   public:
+    explicit Pattern(const OriginAttributesPattern& aPattern)
+        : mPattern(MakeUnique<OriginAttributesPattern>(aPattern)) {}
+
+    explicit Pattern(const nsAString& aJSONPattern)
+        : mPattern(MakeUnique<OriginAttributesPattern>()) {
+      MOZ_ALWAYS_TRUE(mPattern->Init(aJSONPattern));
+    }
+
+    Pattern(const Pattern& aOther)
+        : mPattern(MakeUnique<OriginAttributesPattern>(*aOther.mPattern)) {}
+
+    Pattern(Pattern&& aOther) = default;
+
+    const OriginAttributesPattern& GetPattern() const {
+      MOZ_ASSERT(mPattern);
+
+      return *mPattern;
+    }
+
+    void SetPattern(const OriginAttributesPattern& aPattern) {
+      mPattern = MakeUnique<OriginAttributesPattern>(aPattern);
+    }
+
+    nsString GetJSONPattern() const {
+      MOZ_ASSERT(mPattern);
+
+      nsString result;
+      MOZ_ALWAYS_TRUE(mPattern->ToJSON(result));
+
+      return result;
+    }
+  };
+
+  struct Null {};
+
+  using DataType = Variant<Origin, Prefix, Pattern, Null>;
+
+  DataType mData;
+
+ public:
+  OriginScope() : mData(Null()) {}
+
+  static OriginScope FromOrigin(const nsACString& aOrigin) {
+    return OriginScope(std::move(Origin(aOrigin)));
+  }
+
+  static OriginScope FromPrefix(const nsACString& aPrefix) {
+    return OriginScope(std::move(Prefix(aPrefix)));
+  }
+
+  static OriginScope FromPattern(const OriginAttributesPattern& aPattern) {
+    return OriginScope(std::move(Pattern(aPattern)));
+  }
+
+  static OriginScope FromJSONPattern(const nsAString& aJSONPattern) {
+    return OriginScope(std::move(Pattern(aJSONPattern)));
+  }
+
+  static OriginScope FromNull() { return OriginScope(std::move(Null())); }
+
+  bool IsOrigin() const { return mData.is<Origin>(); }
+
+  bool IsPrefix() const { return mData.is<Prefix>(); }
+
+  bool IsPattern() const { return mData.is<Pattern>(); }
+
+  bool IsNull() const { return mData.is<Null>(); }
+
+  void SetFromOrigin(const nsACString& aOrigin) {
+    mData = AsVariant(Origin(aOrigin));
+  }
+
+  void SetFromPrefix(const nsACString& aPrefix) {
+    mData = AsVariant(Prefix(aPrefix));
+  }
+
+  void SetFromPattern(const OriginAttributesPattern& aPattern) {
+    mData = AsVariant(Pattern(aPattern));
+  }
+
+  void SetFromJSONPattern(const nsAString& aJSONPattern) {
+    mData = AsVariant(Pattern(aJSONPattern));
+  }
+
+  void SetFromNull() { mData = AsVariant(Null()); }
+
+  const nsACString& GetOrigin() const {
+    MOZ_ASSERT(IsOrigin());
+
+    return mData.as<Origin>().GetOrigin();
+  }
+
+  void SetOrigin(const nsACString& aOrigin) {
+    MOZ_ASSERT(IsOrigin());
+
+    mData.as<Origin>().SetOrigin(aOrigin);
+  }
+
+  const nsACString& GetOriginNoSuffix() const {
+    MOZ_ASSERT(IsOrigin() || IsPrefix());
+
+    if (IsOrigin()) {
+      return mData.as<Origin>().GetOriginNoSuffix();
+    }
+    return mData.as<Prefix>().GetOriginNoSuffix();
+  }
+
+  void SetOriginNoSuffix(const nsACString& aOriginNoSuffix) {
+    MOZ_ASSERT(IsPrefix());
+
+    mData.as<Prefix>().SetOriginNoSuffix(aOriginNoSuffix);
+  }
+
+  const OriginAttributesPattern& GetPattern() const {
+    MOZ_ASSERT(IsPattern());
+
+    return mData.as<Pattern>().GetPattern();
+  }
+
+  nsString GetJSONPattern() const {
+    MOZ_ASSERT(IsPattern());
+
+    return mData.as<Pattern>().GetJSONPattern();
+  }
+
+  void SetPattern(const OriginAttributesPattern& aPattern) {
+    MOZ_ASSERT(IsPattern());
+
+    mData.as<Pattern>().SetPattern(aPattern);
+  }
+
+  bool Matches(const OriginScope& aOther) const {
+    struct Matcher {
+      const OriginScope& mThis;
+
+      explicit Matcher(const OriginScope& aThis) : mThis(aThis) {}
+
+      bool operator()(const Origin& aOther) {
+        return mThis.MatchesOrigin(aOther);
+      }
+
+      bool operator()(const Prefix& aOther) {
+        return mThis.MatchesPrefix(aOther);
+      }
+
+      bool operator()(const Pattern& aOther) {
+        return mThis.MatchesPattern(aOther);
+      }
+
+      bool operator()(const Null& aOther) { return true; }
+    };
+
+    return aOther.mData.match(Matcher(*this));
+  }
+
+  OriginScope Clone() { return OriginScope(mData); }
+
+ private:
+  // Move constructors
+  explicit OriginScope(const Origin&& aOrigin) : mData(aOrigin) {}
+
+  explicit OriginScope(const Prefix&& aPrefix) : mData(aPrefix) {}
+
+  explicit OriginScope(const Pattern&& aPattern) : mData(aPattern) {}
+
+  explicit OriginScope(const Null&& aNull) : mData(aNull) {}
+
+  // Copy constructor
+  explicit OriginScope(const DataType& aOther) : mData(aOther) {}
+
+  bool MatchesOrigin(const Origin& aOther) const {
+    struct OriginMatcher {
+      const Origin& mOther;
+
+      explicit OriginMatcher(const Origin& aOther) : mOther(aOther) {}
+
+      bool operator()(const Origin& aThis) {
+        return aThis.GetOrigin().Equals(mOther.GetOrigin());
+      }
+
+      bool operator()(const Prefix& aThis) {
+        return aThis.GetOriginNoSuffix().Equals(mOther.GetOriginNoSuffix());
+      }
+
+      bool operator()(const Pattern& aThis) {
+        return aThis.GetPattern().Matches(mOther.GetAttributes());
+      }
+
+      bool operator()(const Null& aThis) {
+        // Null covers everything.
+        return true;
+      }
+    };
+
+    return mData.match(OriginMatcher(aOther));
+  }
+
+  bool MatchesPrefix(const Prefix& aOther) const {
+    struct PrefixMatcher {
+      const Prefix& mOther;
+
+      explicit PrefixMatcher(const Prefix& aOther) : mOther(aOther) {}
+
+      bool operator()(const Origin& aThis) {
+        return aThis.GetOriginNoSuffix().Equals(mOther.GetOriginNoSuffix());
+      }
+
+      bool operator()(const Prefix& aThis) {
+        return aThis.GetOriginNoSuffix().Equals(mOther.GetOriginNoSuffix());
+      }
+
+      bool operator()(const Pattern& aThis) {
+        // The match will be always true here because any origin attributes
+        // pattern overlaps any origin prefix (an origin prefix targets all
+        // origin attributes).
+        return true;
+      }
+
+      bool operator()(const Null& aThis) {
+        // Null covers everything.
+        return true;
+      }
+    };
+
+    return mData.match(PrefixMatcher(aOther));
+  }
+
+  bool MatchesPattern(const Pattern& aOther) const {
+    struct PatternMatcher {
+      const Pattern& mOther;
+
+      explicit PatternMatcher(const Pattern& aOther) : mOther(aOther) {}
+
+      bool operator()(const Origin& aThis) {
+        return mOther.GetPattern().Matches(aThis.GetAttributes());
+      }
+
+      bool operator()(const Prefix& aThis) {
+        // The match will be always true here because any origin attributes
+        // pattern overlaps any origin prefix (an origin prefix targets all
+        // origin attributes).
+        return true;
+      }
+
+      bool operator()(const Pattern& aThis) {
+        return aThis.GetPattern().Overlaps(mOther.GetPattern());
+      }
+
+      bool operator()(const Null& aThis) {
+        // Null covers everything.
+        return true;
+      }
+    };
+
+    PatternMatcher patternMatcher(aOther);
+    return mData.match(PatternMatcher(aOther));
+  }
+
+  bool operator==(const OriginScope& aOther) = delete;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_originorpatternstring_h__
diff --git a/dom/quota/PQuota.ipdl b/dom/quota/PQuota.ipdl
new file mode 100644
index 0000000000..f34109b239
--- /dev/null
+++ b/dom/quota/PQuota.ipdl
@@ -0,0 +1,180 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PBackground;
+include protocol PQuotaRequest;
+include protocol PQuotaUsageRequest;
+
+include PBackgroundSharedTypes;
+
+include "mozilla/dom/quota/SerializationHelpers.h";
+
+using mozilla::OriginAttributesPattern
+  from "mozilla/OriginAttributes.h";
+
+using mozilla::dom::quota::PersistenceType
+  from "mozilla/dom/quota/PersistenceType.h";
+
+using mozilla::dom::quota::Client::Type
+  from "mozilla/dom/quota/Client.h";
+
+using mozilla::dom::ContentParentId
+  from "mozilla/dom/ipc/IdType.h";
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+struct StorageNameParams
+{
+};
+
+struct StorageInitializedParams
+{
+};
+
+struct TemporaryStorageInitializedParams
+{
+};
+
+struct InitParams
+{
+};
+
+struct InitTemporaryStorageParams
+{
+};
+
+struct InitializePersistentOriginParams
+{
+  PrincipalInfo principalInfo;
+};
+
+struct InitializeTemporaryOriginParams
+{
+  PersistenceType persistenceType;
+  PrincipalInfo principalInfo;
+};
+
+struct GetFullOriginMetadataParams
+{
+  PersistenceType persistenceType;
+  PrincipalInfo principalInfo;
+};
+
+struct AllUsageParams
+{
+  bool getAll;
+};
+
+struct OriginUsageParams
+{
+  PrincipalInfo principalInfo;
+  bool fromMemory;
+};
+
+union UsageRequestParams
+{
+  AllUsageParams;
+  OriginUsageParams;
+};
+
+struct ClearResetOriginParams
+{
+  PrincipalInfo principalInfo;
+  PersistenceType persistenceType;
+  bool persistenceTypeIsExplicit;
+  Type clientType;
+  bool clientTypeIsExplicit;
+};
+
+struct ClearOriginParams
+{
+  ClearResetOriginParams commonParams;
+  bool matchAll;
+};
+
+struct ResetOriginParams
+{
+  ClearResetOriginParams commonParams;
+};
+
+struct ClearDataParams
+{
+  OriginAttributesPattern pattern;
+};
+
+struct ClearAllParams
+{
+};
+
+struct ResetAllParams
+{
+};
+
+struct PersistedParams
+{
+  PrincipalInfo principalInfo;
+};
+
+struct PersistParams
+{
+  PrincipalInfo principalInfo;
+};
+
+struct EstimateParams
+{
+  PrincipalInfo principalInfo;
+};
+
+struct ListOriginsParams
+{
+};
+
+union RequestParams
+{
+  StorageNameParams;
+  StorageInitializedParams;
+  TemporaryStorageInitializedParams;
+  InitParams;
+  InitTemporaryStorageParams;
+  InitializePersistentOriginParams;
+  InitializeTemporaryOriginParams;
+  GetFullOriginMetadataParams;
+  ClearOriginParams;
+  ResetOriginParams;
+  ClearDataParams;
+  ClearAllParams;
+  ResetAllParams;
+  PersistedParams;
+  PersistParams;
+  EstimateParams;
+  ListOriginsParams;
+};
+
+[ManualDealloc, ChildImpl=virtual, ParentImpl=virtual]
+protocol PQuota
+{
+  manager PBackground;
+
+  manages PQuotaRequest;
+  manages PQuotaUsageRequest;
+
+parent:
+  async __delete__();
+
+  async PQuotaUsageRequest(UsageRequestParams params);
+
+  async PQuotaRequest(RequestParams params);
+
+  async StartIdleMaintenance();
+
+  async StopIdleMaintenance();
+
+  async AbortOperationsForProcess(ContentParentId contentParentId);
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/PQuotaRequest.ipdl b/dom/quota/PQuotaRequest.ipdl
new file mode 100644
index 0000000000..b155bda557
--- /dev/null
+++ b/dom/quota/PQuotaRequest.ipdl
@@ -0,0 +1,127 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PQuota;
+
+include "mozilla/dom/quota/SerializationHelpers.h";
+
+using mozilla::dom::quota::FullOriginMetadata
+  from "mozilla/dom/quota/CommonMetadata.h";
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+struct StorageNameResponse
+{
+  nsString name;
+};
+
+struct StorageInitializedResponse
+{
+  bool initialized;
+};
+
+struct TemporaryStorageInitializedResponse
+{
+  bool initialized;
+};
+
+struct InitResponse
+{
+};
+
+struct InitTemporaryStorageResponse
+{
+};
+
+struct InitializePersistentOriginResponse
+{
+  bool created;
+};
+
+struct InitializeTemporaryOriginResponse
+{
+  bool created;
+};
+
+struct GetFullOriginMetadataResponse
+{
+  FullOriginMetadata? maybeFullOriginMetadata;
+};
+
+struct ClearOriginResponse
+{
+};
+
+struct ResetOriginResponse
+{
+};
+
+struct ClearDataResponse
+{
+};
+
+struct ClearAllResponse
+{
+};
+
+struct ResetAllResponse
+{
+};
+
+struct PersistedResponse
+{
+  bool persisted;
+};
+
+struct PersistResponse
+{
+};
+
+struct EstimateResponse
+{
+  uint64_t usage;
+  uint64_t limit;
+};
+
+struct ListOriginsResponse
+{
+  nsCString[] origins;
+};
+
+union RequestResponse
+{
+  nsresult;
+  StorageNameResponse;
+  StorageInitializedResponse;
+  TemporaryStorageInitializedResponse;
+  InitResponse;
+  InitTemporaryStorageResponse;
+  InitializePersistentOriginResponse;
+  InitializeTemporaryOriginResponse;
+  GetFullOriginMetadataResponse;
+  ClearOriginResponse;
+  ResetOriginResponse;
+  ClearDataResponse;
+  ClearAllResponse;
+  ResetAllResponse;
+  PersistedResponse;
+  PersistResponse;
+  EstimateResponse;
+  ListOriginsResponse;
+};
+
+[ManualDealloc, ChildImpl=virtual, ParentImpl=virtual]
+protocol PQuotaRequest
+{
+  manager PQuota;
+
+child:
+  async __delete__(RequestResponse response);
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/PQuotaUsageRequest.ipdl b/dom/quota/PQuotaUsageRequest.ipdl
new file mode 100644
index 0000000000..26401c84e6
--- /dev/null
+++ b/dom/quota/PQuotaUsageRequest.ipdl
@@ -0,0 +1,51 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PQuota;
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+struct OriginUsage
+{
+  nsCString origin;
+  bool persisted;
+  uint64_t usage;
+  uint64_t lastAccessed;
+};
+
+struct AllUsageResponse
+{
+  OriginUsage[] originUsages;
+};
+
+struct OriginUsageResponse
+{
+  uint64_t usage;
+  uint64_t fileUsage;
+};
+
+union UsageRequestResponse
+{
+  nsresult;
+  AllUsageResponse;
+  OriginUsageResponse;
+};
+
+[ManualDealloc, ChildImpl=virtual, ParentImpl=virtual]
+protocol PQuotaUsageRequest
+{
+  manager PQuota;
+
+parent:
+  async Cancel();
+
+child:
+  async __delete__(UsageRequestResponse response);
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/PRemoteQuotaObject.ipdl b/dom/quota/PRemoteQuotaObject.ipdl
new file mode 100644
index 0000000000..f0221d7b9c
--- /dev/null
+++ b/dom/quota/PRemoteQuotaObject.ipdl
@@ -0,0 +1,22 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+sync protocol PRemoteQuotaObject
+{
+ parent:
+  // This must be synchronous because we don't have quota file stream wrappers
+  // which would be fully asynchronous (non-blocking). Given that, this message
+  // should never be sent on the main thread or the PBackground thread or a DOM
+  // worker thread.
+  sync MaybeUpdateSize(int64_t size, bool truncate)
+      returns(bool result);
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/PersistenceType.cpp b/dom/quota/PersistenceType.cpp
new file mode 100644
index 0000000000..637175c886
--- /dev/null
+++ b/dom/quota/PersistenceType.cpp
@@ -0,0 +1,202 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "PersistenceType.h"
+
+#include <utility>
+#include "nsIFile.h"
+#include "nsLiteralString.h"
+#include "nsString.h"
+
+namespace mozilla::dom::quota {
+
+namespace {
+
+constexpr auto kPersistentCString = "persistent"_ns;
+constexpr auto kTemporaryCString = "temporary"_ns;
+constexpr auto kDefaultCString = "default"_ns;
+
+constexpr auto kPermanentString = u"permanent"_ns;
+constexpr auto kTemporaryString = u"temporary"_ns;
+constexpr auto kDefaultString = u"default"_ns;
+
+static_assert(PERSISTENCE_TYPE_PERSISTENT == 0 &&
+                  PERSISTENCE_TYPE_TEMPORARY == 1 &&
+                  PERSISTENCE_TYPE_DEFAULT == 2 &&
+                  PERSISTENCE_TYPE_INVALID == 3,
+              "Incorrect enum values!");
+
+template <PersistenceType type>
+struct PersistenceTypeTraits;
+
+template <>
+struct PersistenceTypeTraits<PERSISTENCE_TYPE_PERSISTENT> {
+  template <typename T>
+  static T To();
+
+  static bool From(const nsACString& aString) {
+    return aString == kPersistentCString;
+  }
+
+  static bool From(const int32_t aInt32) { return aInt32 == 0; }
+
+  static bool From(nsIFile& aFile) {
+    nsAutoString leafName;
+    MOZ_ALWAYS_SUCCEEDS(aFile.GetLeafName(leafName));
+    return leafName == kPermanentString;
+  }
+};
+
+template <>
+nsLiteralCString
+PersistenceTypeTraits<PERSISTENCE_TYPE_PERSISTENT>::To<nsLiteralCString>() {
+  return kPersistentCString;
+}
+
+template <>
+struct PersistenceTypeTraits<PERSISTENCE_TYPE_TEMPORARY> {
+  template <typename T>
+  static T To();
+
+  static bool From(const nsACString& aString) {
+    return aString == kTemporaryCString;
+  }
+
+  static bool From(const int32_t aInt32) { return aInt32 == 1; }
+
+  static bool From(nsIFile& aFile) {
+    nsAutoString leafName;
+    MOZ_ALWAYS_SUCCEEDS(aFile.GetLeafName(leafName));
+    return leafName == kTemporaryString;
+  }
+};
+
+template <>
+nsLiteralCString
+PersistenceTypeTraits<PERSISTENCE_TYPE_TEMPORARY>::To<nsLiteralCString>() {
+  return kTemporaryCString;
+}
+
+template <>
+struct PersistenceTypeTraits<PERSISTENCE_TYPE_DEFAULT> {
+  template <typename T>
+  static T To();
+
+  static bool From(const nsACString& aString) {
+    return aString == kDefaultCString;
+  }
+
+  static bool From(const int32_t aInt32) { return aInt32 == 2; }
+
+  static bool From(nsIFile& aFile) {
+    nsAutoString leafName;
+    MOZ_ALWAYS_SUCCEEDS(aFile.GetLeafName(leafName));
+    return leafName == kDefaultString;
+  }
+};
+
+template <>
+nsLiteralCString
+PersistenceTypeTraits<PERSISTENCE_TYPE_DEFAULT>::To<nsLiteralCString>() {
+  return kDefaultCString;
+}
+
+template <typename T>
+Maybe<T> TypeTo_impl(const PersistenceType aPersistenceType) {
+  switch (aPersistenceType) {
+    case PERSISTENCE_TYPE_PERSISTENT:
+      return Some(PersistenceTypeTraits<PERSISTENCE_TYPE_PERSISTENT>::To<T>());
+
+    case PERSISTENCE_TYPE_TEMPORARY:
+      return Some(PersistenceTypeTraits<PERSISTENCE_TYPE_TEMPORARY>::To<T>());
+
+    case PERSISTENCE_TYPE_DEFAULT:
+      return Some(PersistenceTypeTraits<PERSISTENCE_TYPE_DEFAULT>::To<T>());
+
+    default:
+      return Nothing();
+  }
+}
+
+template <typename T>
+Maybe<PersistenceType> TypeFrom_impl(T& aData) {
+  if (PersistenceTypeTraits<PERSISTENCE_TYPE_PERSISTENT>::From(aData)) {
+    return Some(PERSISTENCE_TYPE_PERSISTENT);
+  }
+
+  if (PersistenceTypeTraits<PERSISTENCE_TYPE_TEMPORARY>::From(aData)) {
+    return Some(PERSISTENCE_TYPE_TEMPORARY);
+  }
+
+  if (PersistenceTypeTraits<PERSISTENCE_TYPE_DEFAULT>::From(aData)) {
+    return Some(PERSISTENCE_TYPE_DEFAULT);
+  }
+
+  return Nothing();
+}
+
+void BadPersistenceType() { MOZ_CRASH("Bad persistence type value!"); }
+
+}  // namespace
+
+bool IsValidPersistenceType(const PersistenceType aPersistenceType) {
+  switch (aPersistenceType) {
+    case PERSISTENCE_TYPE_PERSISTENT:
+    case PERSISTENCE_TYPE_TEMPORARY:
+    case PERSISTENCE_TYPE_DEFAULT:
+      return true;
+
+    default:
+      return false;
+  }
+}
+
+bool IsBestEffortPersistenceType(const PersistenceType aPersistenceType) {
+  switch (aPersistenceType) {
+    case PERSISTENCE_TYPE_TEMPORARY:
+    case PERSISTENCE_TYPE_DEFAULT:
+      return true;
+
+    case PERSISTENCE_TYPE_PERSISTENT:
+    case PERSISTENCE_TYPE_INVALID:
+    default:
+      return false;
+  }
+}
+
+nsLiteralCString PersistenceTypeToString(
+    const PersistenceType aPersistenceType) {
+  const auto maybeString = TypeTo_impl<nsLiteralCString>(aPersistenceType);
+  if (maybeString.isNothing()) {
+    BadPersistenceType();
+  }
+  return maybeString.value();
+}
+
+Maybe<PersistenceType> PersistenceTypeFromString(const nsACString& aString,
+                                                 const fallible_t&) {
+  return TypeFrom_impl(aString);
+}
+
+PersistenceType PersistenceTypeFromString(const nsACString& aString) {
+  const auto maybePersistenceType = TypeFrom_impl(aString);
+  if (maybePersistenceType.isNothing()) {
+    BadPersistenceType();
+  }
+  return maybePersistenceType.value();
+}
+
+Maybe<PersistenceType> PersistenceTypeFromInt32(const int32_t aInt32,
+                                                const fallible_t&) {
+  return TypeFrom_impl(aInt32);
+}
+
+Maybe<PersistenceType> PersistenceTypeFromFile(nsIFile& aFile,
+                                               const fallible_t&) {
+  return TypeFrom_impl(aFile);
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/PersistenceType.h b/dom/quota/PersistenceType.h
new file mode 100644
index 0000000000..0fcab4ff63
--- /dev/null
+++ b/dom/quota/PersistenceType.h
@@ -0,0 +1,69 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_persistencetype_h__
+#define mozilla_dom_quota_persistencetype_h__
+
+#include <cstdint>
+#include "mozilla/Assertions.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/fallible.h"
+#include "nsStringFwd.h"
+
+class nsIFile;
+
+namespace mozilla::dom::quota {
+
+enum PersistenceType {
+  PERSISTENCE_TYPE_PERSISTENT = 0,
+  PERSISTENCE_TYPE_TEMPORARY,
+  PERSISTENCE_TYPE_DEFAULT,
+
+  // Only needed for IPC serialization helper, should never be used in code.
+  PERSISTENCE_TYPE_INVALID
+};
+
+static const PersistenceType kAllPersistenceTypes[] = {
+    PERSISTENCE_TYPE_PERSISTENT, PERSISTENCE_TYPE_TEMPORARY,
+    PERSISTENCE_TYPE_DEFAULT};
+
+static const PersistenceType kBestEffortPersistenceTypes[] = {
+    PERSISTENCE_TYPE_TEMPORARY, PERSISTENCE_TYPE_DEFAULT};
+
+bool IsValidPersistenceType(PersistenceType aPersistenceType);
+
+bool IsBestEffortPersistenceType(const PersistenceType aPersistenceType);
+
+nsLiteralCString PersistenceTypeToString(PersistenceType aPersistenceType);
+
+Maybe<PersistenceType> PersistenceTypeFromString(const nsACString& aString,
+                                                 const fallible_t&);
+
+PersistenceType PersistenceTypeFromString(const nsACString& aString);
+
+Maybe<PersistenceType> PersistenceTypeFromInt32(int32_t aInt32,
+                                                const fallible_t&);
+
+// aFile is expected to be a repository directory (not some file or directory
+// within that).
+Maybe<PersistenceType> PersistenceTypeFromFile(nsIFile& aFile,
+                                               const fallible_t&);
+
+inline PersistenceType ComplementaryPersistenceType(
+    const PersistenceType aPersistenceType) {
+  MOZ_ASSERT(aPersistenceType == PERSISTENCE_TYPE_DEFAULT ||
+             aPersistenceType == PERSISTENCE_TYPE_TEMPORARY);
+
+  if (aPersistenceType == PERSISTENCE_TYPE_DEFAULT) {
+    return PERSISTENCE_TYPE_TEMPORARY;
+  }
+
+  return PERSISTENCE_TYPE_DEFAULT;
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_persistencetype_h__
diff --git a/dom/quota/QMResult.cpp b/dom/quota/QMResult.cpp
new file mode 100644
index 0000000000..1b743679ad
--- /dev/null
+++ b/dom/quota/QMResult.cpp
@@ -0,0 +1,26 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QMResult.h"
+
+#ifdef QM_ERROR_STACKS_ENABLED
+#  include "mozilla/Atomics.h"
+#endif
+
+namespace mozilla {
+
+#ifdef QM_ERROR_STACKS_ENABLED
+namespace {
+
+static Atomic<uint64_t> gLastStackId{0};
+
+}
+
+QMResult::QMResult(nsresult aNSResult)
+    : mStackId(++gLastStackId), mFrameId(1), mNSResult(aNSResult) {}
+#endif
+
+}  // namespace mozilla
diff --git a/dom/quota/QMResult.h b/dom/quota/QMResult.h
new file mode 100644
index 0000000000..f47c82584e
--- /dev/null
+++ b/dom/quota/QMResult.h
@@ -0,0 +1,58 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_QMRESULT_H_
+#define DOM_QUOTA_QMRESULT_H_
+
+#include "ErrorList.h"
+#include "mozilla/dom/quota/Config.h"
+#include "mozilla/dom/quota/ForwardDecls.h"
+
+namespace mozilla {
+
+#ifdef QM_ERROR_STACKS_ENABLED
+// A wrapped nsresult, primarily intended for use along with mozilla::Result
+// and QM_TRY macros. The wrapper contains stack id and frame id which are
+// reported in LogError besides the error result itself.
+//
+// XXX Document the general situation more, bug 1709777.
+class QMResult {
+  uint64_t mStackId;
+  uint32_t mFrameId;
+  nsresult mNSResult;
+
+ public:
+  QMResult() : QMResult(NS_OK) {}
+
+  explicit QMResult(nsresult aNSResult);
+
+  uint64_t StackId() const { return mStackId; }
+
+  uint32_t FrameId() const { return mFrameId; }
+
+  nsresult NSResult() const { return mNSResult; }
+
+  /**
+   * Propagate the result.
+   *
+   * This is used by GenericErrorResult<QMResult> to create a propagated
+   * result.
+   */
+  QMResult Propagate() const {
+    return QMResult{mStackId, mFrameId + 1, mNSResult};
+  }
+
+ private:
+  QMResult(uint64_t aStackId, uint32_t aFrameId, nsresult aNSResult)
+      : mStackId(aStackId), mFrameId(aFrameId), mNSResult(aNSResult) {}
+};
+#endif
+
+inline QMResult ToQMResult(nsresult aValue) { return QMResult(aValue); }
+
+}  // namespace mozilla
+
+#endif
diff --git a/dom/quota/QuotaCommon.cpp b/dom/quota/QuotaCommon.cpp
new file mode 100644
index 0000000000..e2df8a1082
--- /dev/null
+++ b/dom/quota/QuotaCommon.cpp
@@ -0,0 +1,639 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/QuotaCommon.h"
+
+#ifdef QM_ERROR_STACKS_ENABLED
+#  include "base/process_util.h"
+#endif
+#include "mozIStorageConnection.h"
+#include "mozIStorageStatement.h"
+#include "mozilla/ErrorNames.h"
+#include "mozilla/MozPromise.h"
+#include "mozilla/Logging.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TelemetryComms.h"
+#include "mozilla/TelemetryEventEnums.h"
+#include "mozilla/TextUtils.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/dom/quota/ScopedLogExtraInfo.h"
+#include "nsIConsoleService.h"
+#include "nsIFile.h"
+#include "nsServiceManagerUtils.h"
+#include "nsStringFlags.h"
+#include "nsTStringRepr.h"
+#include "nsUnicharUtils.h"
+#include "nsXPCOM.h"
+#include "nsXULAppAPI.h"
+
+#ifdef XP_WIN
+#  include "mozilla/Atomics.h"
+#  include "mozilla/ipc/BackgroundParent.h"
+#  include "mozilla/StaticPrefs_dom.h"
+#  include "nsILocalFileWin.h"
+#endif
+
+namespace mozilla {
+
+RefPtr<BoolPromise> CreateAndRejectBoolPromise(const char* aFunc,
+                                               nsresult aRv) {
+  return CreateAndRejectMozPromise<BoolPromise>(aFunc, aRv);
+}
+
+RefPtr<Int64Promise> CreateAndRejectInt64Promise(const char* aFunc,
+                                                 nsresult aRv) {
+  return CreateAndRejectMozPromise<Int64Promise>(aFunc, aRv);
+}
+
+RefPtr<BoolPromise> CreateAndRejectBoolPromiseFromQMResult(
+    const char* aFunc, const QMResult& aRv) {
+  return CreateAndRejectMozPromise<BoolPromise>(aFunc, aRv);
+}
+
+namespace dom::quota {
+
+using namespace mozilla::Telemetry;
+
+namespace {
+
+#ifdef DEBUG
+constexpr auto kDSStoreFileName = u".DS_Store"_ns;
+constexpr auto kDesktopFileName = u".desktop"_ns;
+constexpr auto kDesktopIniFileName = u"desktop.ini"_ns;
+constexpr auto kThumbsDbFileName = u"thumbs.db"_ns;
+#endif
+
+#ifdef XP_WIN
+Atomic<int32_t> gUseDOSDevicePathSyntax(-1);
+#endif
+
+LazyLogModule gLogger("QuotaManager");
+
+void AnonymizeCString(nsACString& aCString, uint32_t aStart) {
+  MOZ_ASSERT(!aCString.IsEmpty());
+  MOZ_ASSERT(aStart < aCString.Length());
+
+  char* iter = aCString.BeginWriting() + aStart;
+  char* end = aCString.EndWriting();
+
+  while (iter != end) {
+    char c = *iter;
+
+    if (IsAsciiAlpha(c)) {
+      *iter = 'a';
+    } else if (IsAsciiDigit(c)) {
+      *iter = 'D';
+    }
+
+    ++iter;
+  }
+}
+
+}  // namespace
+
+const char kQuotaGenericDelimiter = '|';
+
+#ifdef NIGHTLY_BUILD
+const nsLiteralCString kQuotaInternalError = "internal"_ns;
+const nsLiteralCString kQuotaExternalError = "external"_ns;
+#endif
+
+LogModule* GetQuotaManagerLogger() { return gLogger; }
+
+void AnonymizeCString(nsACString& aCString) {
+  if (aCString.IsEmpty()) {
+    return;
+  }
+  AnonymizeCString(aCString, /* aStart */ 0);
+}
+
+void AnonymizeOriginString(nsACString& aOriginString) {
+  if (aOriginString.IsEmpty()) {
+    return;
+  }
+
+  int32_t start = aOriginString.FindChar(':');
+  if (start < 0) {
+    start = 0;
+  }
+
+  AnonymizeCString(aOriginString, start);
+}
+
+#ifdef XP_WIN
+void CacheUseDOSDevicePathSyntaxPrefValue() {
+  MOZ_ASSERT(XRE_IsParentProcess());
+  ::mozilla::ipc::AssertIsOnBackgroundThread();
+
+  if (gUseDOSDevicePathSyntax == -1) {
+    bool useDOSDevicePathSyntax =
+        StaticPrefs::dom_quotaManager_useDOSDevicePathSyntax_DoNotUseDirectly();
+    gUseDOSDevicePathSyntax = useDOSDevicePathSyntax ? 1 : 0;
+  }
+}
+#endif
+
+Result<nsCOMPtr<nsIFile>, nsresult> QM_NewLocalFile(const nsAString& aPath) {
+  QM_TRY_UNWRAP(
+      auto file,
+      MOZ_TO_RESULT_INVOKE_TYPED(nsCOMPtr<nsIFile>, NS_NewLocalFile, aPath,
+                                 /* aFollowLinks */ false),
+      QM_PROPAGATE, [&aPath](const nsresult rv) {
+        QM_WARNING("Failed to construct a file for path (%s)",
+                   NS_ConvertUTF16toUTF8(aPath).get());
+      });
+
+#ifdef XP_WIN
+  MOZ_ASSERT(gUseDOSDevicePathSyntax != -1);
+
+  if (gUseDOSDevicePathSyntax) {
+    QM_TRY_INSPECT(
+        const auto& winFile,
+        MOZ_TO_RESULT_GET_TYPED(nsCOMPtr<nsILocalFileWin>,
+                                MOZ_SELECT_OVERLOAD(do_QueryInterface), file));
+
+    MOZ_ASSERT(winFile);
+    winFile->SetUseDOSDevicePathSyntax(true);
+  }
+#endif
+
+  return file;
+}
+
+nsDependentCSubstring GetLeafName(const nsACString& aPath) {
+  nsACString::const_iterator start, end;
+  aPath.BeginReading(start);
+  aPath.EndReading(end);
+
+  bool found = RFindInReadable("/"_ns, start, end);
+  if (found) {
+    start = end;
+  }
+
+  aPath.EndReading(end);
+
+  return nsDependentCSubstring(start.get(), end.get());
+}
+
+Result<nsCOMPtr<nsIFile>, nsresult> CloneFileAndAppend(
+    nsIFile& aDirectory, const nsAString& aPathElement) {
+  QM_TRY_UNWRAP(auto resultFile, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                     nsCOMPtr<nsIFile>, aDirectory, Clone));
+
+  QM_TRY(MOZ_TO_RESULT(resultFile->Append(aPathElement)));
+
+  return resultFile;
+}
+
+Result<nsIFileKind, nsresult> GetDirEntryKind(nsIFile& aFile) {
+  // Callers call this function without checking if the directory already
+  // exists (idempotent usage). QM_OR_ELSE_WARN_IF is not used here since we
+  // just want to log NS_ERROR_FILE_NOT_FOUND and NS_ERROR_FILE_FS_CORRUPTED
+  // results and not spam the reports.
+  QM_TRY_RETURN(QM_OR_ELSE_LOG_VERBOSE_IF(
+      MOZ_TO_RESULT_INVOKE_MEMBER(aFile, IsDirectory)
+          .map([](const bool isDirectory) {
+            return isDirectory ? nsIFileKind::ExistsAsDirectory
+                               : nsIFileKind::ExistsAsFile;
+          }),
+      ([](const nsresult rv) {
+        return rv == NS_ERROR_FILE_NOT_FOUND ||
+               // We treat NS_ERROR_FILE_FS_CORRUPTED as if the file did not
+               // exist at all.
+               rv == NS_ERROR_FILE_FS_CORRUPTED;
+      }),
+      ErrToOk<nsIFileKind::DoesNotExist>));
+}
+
+Result<nsCOMPtr<mozIStorageStatement>, nsresult> CreateStatement(
+    mozIStorageConnection& aConnection, const nsACString& aStatementString) {
+  QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+      nsCOMPtr<mozIStorageStatement>, aConnection, CreateStatement,
+      aStatementString));
+}
+
+template <SingleStepResult ResultHandling>
+Result<SingleStepSuccessType<ResultHandling>, nsresult> ExecuteSingleStep(
+    nsCOMPtr<mozIStorageStatement>&& aStatement) {
+  QM_TRY_INSPECT(const bool& hasResult,
+                 MOZ_TO_RESULT_INVOKE_MEMBER(aStatement, ExecuteStep));
+
+  if constexpr (ResultHandling == SingleStepResult::AssertHasResult) {
+    MOZ_ASSERT(hasResult);
+    (void)hasResult;
+
+    return WrapNotNullUnchecked(std::move(aStatement));
+  } else {
+    return hasResult ? std::move(aStatement) : nullptr;
+  }
+}
+
+template Result<SingleStepSuccessType<SingleStepResult::AssertHasResult>,
+                nsresult>
+ExecuteSingleStep<SingleStepResult::AssertHasResult>(
+    nsCOMPtr<mozIStorageStatement>&&);
+
+template Result<SingleStepSuccessType<SingleStepResult::ReturnNullIfNoResult>,
+                nsresult>
+ExecuteSingleStep<SingleStepResult::ReturnNullIfNoResult>(
+    nsCOMPtr<mozIStorageStatement>&&);
+
+template <SingleStepResult ResultHandling>
+Result<SingleStepSuccessType<ResultHandling>, nsresult>
+CreateAndExecuteSingleStepStatement(mozIStorageConnection& aConnection,
+                                    const nsACString& aStatementString) {
+  QM_TRY_UNWRAP(auto stmt, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                               nsCOMPtr<mozIStorageStatement>, aConnection,
+                               CreateStatement, aStatementString));
+
+  return ExecuteSingleStep<ResultHandling>(std::move(stmt));
+}
+
+template Result<SingleStepSuccessType<SingleStepResult::AssertHasResult>,
+                nsresult>
+CreateAndExecuteSingleStepStatement<SingleStepResult::AssertHasResult>(
+    mozIStorageConnection& aConnection, const nsACString& aStatementString);
+
+template Result<SingleStepSuccessType<SingleStepResult::ReturnNullIfNoResult>,
+                nsresult>
+CreateAndExecuteSingleStepStatement<SingleStepResult::ReturnNullIfNoResult>(
+    mozIStorageConnection& aConnection, const nsACString& aStatementString);
+
+namespace detail {
+
+// Given aPath of /foo/bar/baz and aRelativePath of /bar/baz, returns the
+// absolute portion of aPath /foo by removing the common suffix from aPath.
+nsDependentCSubstring GetTreeBase(const nsLiteralCString& aPath,
+                                  const nsLiteralCString& aRelativePath) {
+  MOZ_ASSERT(StringEndsWith(aPath, aRelativePath));
+  return Substring(aPath, 0, aPath.Length() - aRelativePath.Length());
+}
+
+nsDependentCSubstring GetSourceTreeBase() {
+  static constexpr auto thisSourceFileRelativePath =
+      "/dom/quota/QuotaCommon.cpp"_ns;
+
+  return GetTreeBase(nsLiteralCString(__FILE__), thisSourceFileRelativePath);
+}
+
+nsDependentCSubstring GetObjdirDistIncludeTreeBase(
+    const nsLiteralCString& aQuotaCommonHPath) {
+  static constexpr auto quotaCommonHSourceFileRelativePath =
+      "/mozilla/dom/quota/QuotaCommon.h"_ns;
+
+  return GetTreeBase(aQuotaCommonHPath, quotaCommonHSourceFileRelativePath);
+}
+
+static constexpr auto kSourceFileRelativePathMap =
+    std::array<std::pair<nsLiteralCString, nsLiteralCString>, 1>{
+        {{"mozilla/dom/LocalStorageCommon.h"_ns,
+          "dom/localstorage/LocalStorageCommon.h"_ns}}};
+
+nsDependentCSubstring MakeSourceFileRelativePath(
+    const nsACString& aSourceFilePath) {
+  static constexpr auto error = "ERROR"_ns;
+  static constexpr auto mozillaRelativeBase = "mozilla/"_ns;
+
+  static const auto sourceTreeBase = GetSourceTreeBase();
+
+  if (MOZ_LIKELY(StringBeginsWith(aSourceFilePath, sourceTreeBase))) {
+    return Substring(aSourceFilePath, sourceTreeBase.Length() + 1);
+  }
+
+  // The source file could have been exported to the OBJDIR/dist/include
+  // directory, so we need to check that case as well.
+  static const auto objdirDistIncludeTreeBase = GetObjdirDistIncludeTreeBase();
+
+  if (MOZ_LIKELY(
+          StringBeginsWith(aSourceFilePath, objdirDistIncludeTreeBase))) {
+    const auto sourceFileRelativePath =
+        Substring(aSourceFilePath, objdirDistIncludeTreeBase.Length() + 1);
+
+    // Exported source files don't have to use the same directory structure as
+    // original source files. Check if we have a mapping for the exported
+    // source file.
+    const auto foundIt = std::find_if(
+        kSourceFileRelativePathMap.cbegin(), kSourceFileRelativePathMap.cend(),
+        [&sourceFileRelativePath](const auto& entry) {
+          return entry.first == sourceFileRelativePath;
+        });
+
+    if (MOZ_UNLIKELY(foundIt != kSourceFileRelativePathMap.cend())) {
+      return Substring(foundIt->second, 0);
+    }
+
+    // If we don't have a mapping for it, just remove the mozilla/ prefix
+    // (if there's any).
+    if (MOZ_LIKELY(
+            StringBeginsWith(sourceFileRelativePath, mozillaRelativeBase))) {
+      return Substring(sourceFileRelativePath, mozillaRelativeBase.Length());
+    }
+
+    // At this point, we don't know how to transform the relative path of the
+    // exported source file back to the relative path of the original source
+    // file. This can happen when QM_TRY is used in an exported nsIFoo.h file.
+    // If you really need to use QM_TRY there, consider adding a new mapping
+    // for the exported source file.
+    return sourceFileRelativePath;
+  }
+
+  nsCString::const_iterator begin, end;
+  if (RFindInReadable("/"_ns, aSourceFilePath.BeginReading(begin),
+                      aSourceFilePath.EndReading(end))) {
+    // Use the basename as a fallback, to avoid exposing any user parts of the
+    // path.
+    ++begin;
+    return Substring(begin, aSourceFilePath.EndReading(end));
+  }
+
+  return nsDependentCSubstring{static_cast<mozilla::Span<const char>>(
+      static_cast<const nsCString&>(error))};
+}
+
+}  // namespace detail
+
+#ifdef QM_LOG_ERROR_ENABLED
+#  ifdef QM_ERROR_STACKS_ENABLED
+void LogError(const nsACString& aExpr, const ResultType& aResult,
+              const nsACString& aSourceFilePath, const int32_t aSourceFileLine,
+              const Severity aSeverity)
+#  else
+void LogError(const nsACString& aExpr, const Maybe<nsresult> aMaybeRv,
+              const nsACString& aSourceFilePath, const int32_t aSourceFileLine,
+              const Severity aSeverity)
+#  endif
+{
+  // TODO: Add MOZ_LOG support, bug 1711661.
+
+  // We have to ignore failures with the Verbose severity until we have support
+  // for MOZ_LOG.
+  if (aSeverity == Severity::Verbose) {
+    return;
+  }
+
+  nsAutoCString context;
+
+#  ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+
+  if (const auto contextIt = extraInfoMap.find(ScopedLogExtraInfo::kTagContext);
+      contextIt != extraInfoMap.cend()) {
+    context = *contextIt->second;
+  }
+#  endif
+
+  const auto severityString = [&aSeverity]() -> nsLiteralCString {
+    switch (aSeverity) {
+      case Severity::Error:
+        return "ERROR"_ns;
+      case Severity::Warning:
+        return "WARNING"_ns;
+      case Severity::Info:
+        return "INFO"_ns;
+      case Severity::Verbose:
+        return "VERBOSE"_ns;
+    }
+    MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Bad severity value!");
+  }();
+
+  Maybe<nsresult> maybeRv;
+
+#  ifdef QM_ERROR_STACKS_ENABLED
+  if (aResult.is<QMResult>()) {
+    maybeRv = Some(aResult.as<QMResult>().NSResult());
+  } else if (aResult.is<nsresult>()) {
+    maybeRv = Some(aResult.as<nsresult>());
+  }
+#  else
+  maybeRv = aMaybeRv;
+#  endif
+
+  nsAutoCString rvCode;
+  nsAutoCString rvName;
+
+  if (maybeRv) {
+    nsresult rv = *maybeRv;
+
+    rvCode = nsPrintfCString("0x%" PRIX32, static_cast<uint32_t>(rv));
+
+    // XXX NS_ERROR_MODULE_WIN32 should be handled in GetErrorName directly.
+    if (NS_ERROR_GET_MODULE(rv) == NS_ERROR_MODULE_WIN32) {
+      // XXX We could also try to get the Win32 error name here.
+      rvName = nsPrintfCString(
+          "NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_WIN32, 0x%" PRIX16 ")",
+          NS_ERROR_GET_CODE(rv));
+    } else {
+      mozilla::GetErrorName(rv, rvName);
+    }
+  }
+
+#  ifdef QM_ERROR_STACKS_ENABLED
+  nsAutoCString frameIdString;
+  nsAutoCString stackIdString;
+  nsAutoCString processIdString;
+
+  if (aResult.is<QMResult>()) {
+    const QMResult& result = aResult.as<QMResult>();
+    frameIdString = IntToCString(result.FrameId());
+    stackIdString = IntToCString(result.StackId());
+    processIdString =
+        IntToCString(static_cast<uint32_t>(base::GetCurrentProcId()));
+  }
+#  endif
+
+  nsAutoCString extraInfosString;
+
+  if (!rvCode.IsEmpty()) {
+    extraInfosString.Append(" failed with resultCode "_ns + rvCode);
+  }
+
+  if (!rvName.IsEmpty()) {
+    extraInfosString.Append(", resultName "_ns + rvName);
+  }
+
+#  ifdef QM_ERROR_STACKS_ENABLED
+  if (!frameIdString.IsEmpty()) {
+    extraInfosString.Append(", frameId "_ns + frameIdString);
+  }
+
+  if (!stackIdString.IsEmpty()) {
+    extraInfosString.Append(", stackId "_ns + stackIdString);
+  }
+
+  if (!processIdString.IsEmpty()) {
+    extraInfosString.Append(", processId "_ns + processIdString);
+  }
+#  endif
+
+#  ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  for (const auto& item : extraInfoMap) {
+    extraInfosString.Append(", "_ns + nsDependentCString(item.first) + " "_ns +
+                            *item.second);
+  }
+#  endif
+
+  const auto sourceFileRelativePath =
+      detail::MakeSourceFileRelativePath(aSourceFilePath);
+
+#  ifdef QM_LOG_ERROR_TO_CONSOLE_ENABLED
+  NS_DebugBreak(
+      NS_DEBUG_WARNING,
+      nsAutoCString("QM_TRY failure ("_ns + severityString + ")"_ns).get(),
+      (extraInfosString.IsEmpty() ? nsPromiseFlatCString(aExpr)
+                                  : static_cast<const nsCString&>(nsAutoCString(
+                                        aExpr + extraInfosString)))
+          .get(),
+      nsPromiseFlatCString(sourceFileRelativePath).get(), aSourceFileLine);
+#  endif
+
+#  ifdef QM_LOG_ERROR_TO_BROWSER_CONSOLE_ENABLED
+  // XXX We might want to allow reporting to the browsing console even when
+  // there's no context in future once we are sure that it can't spam the
+  // browser console or when we have special about:quotamanager for the
+  // reporting (instead of the browsing console).
+  // Another option is to keep the current check and rely on MOZ_LOG reporting
+  // in future once that's available.
+  if (!context.IsEmpty()) {
+    nsCOMPtr<nsIConsoleService> console =
+        do_GetService(NS_CONSOLESERVICE_CONTRACTID);
+    if (console) {
+      NS_ConvertUTF8toUTF16 message(
+          "QM_TRY failure ("_ns + severityString + ")"_ns + ": '"_ns + aExpr +
+          extraInfosString + "', file "_ns + sourceFileRelativePath + ":"_ns +
+          IntToCString(aSourceFileLine));
+
+      // The concatenation above results in a message like:
+      // QM_TRY failure (ERROR): 'MaybeRemoveLocalStorageArchiveTmpFile() failed
+      // with resultCode 0x80004005, resultName NS_ERROR_FAILURE, frameId 1,
+      // stackId 1, processId 53978, context Initialization::Storage', file
+      // dom/quota/ActorsParent.cpp:6029
+
+      console->LogStringMessage(message.get());
+    }
+  }
+#  endif
+
+#  ifdef QM_LOG_ERROR_TO_TELEMETRY_ENABLED
+  if (!context.IsEmpty()) {
+    // For now, we don't include aExpr in the telemetry event. It might help to
+    // match locations across versions, but they might be large.
+    auto extra = Some([&] {
+      auto res = CopyableTArray<EventExtraEntry>{};
+      res.SetCapacity(9);
+
+      res.AppendElement(EventExtraEntry{"context"_ns, nsCString{context}});
+
+#    ifdef QM_ERROR_STACKS_ENABLED
+      if (!frameIdString.IsEmpty()) {
+        res.AppendElement(
+            EventExtraEntry{"frame_id"_ns, nsCString{frameIdString}});
+      }
+
+      if (!processIdString.IsEmpty()) {
+        res.AppendElement(
+            EventExtraEntry{"process_id"_ns, nsCString{processIdString}});
+      }
+#    endif
+
+      if (!rvName.IsEmpty()) {
+        res.AppendElement(EventExtraEntry{"result"_ns, nsCString{rvName}});
+      }
+
+      // Here, we are generating thread local sequence number and thread Id
+      // information which could be useful for summarizing and categorizing
+      // log statistics in QM_TRY stack propagation scripts. Since, this is
+      // a thread local object, we do not need to worry about data races.
+      static MOZ_THREAD_LOCAL(uint32_t) sSequenceNumber;
+
+      // This would be initialized once, all subsequent calls would be a no-op.
+      MOZ_ALWAYS_TRUE(sSequenceNumber.init());
+
+      // sequence number should always starts at number 1.
+      // `sSequenceNumber` gets initialized to 0; so we have to increment here.
+      const auto newSeqNum = sSequenceNumber.get() + 1;
+      const auto threadId =
+          mozilla::baseprofiler::profiler_current_thread_id().ToNumber();
+
+      const auto threadIdAndSequence =
+          (static_cast<uint64_t>(threadId) << 32) | (newSeqNum & 0xFFFFFFFF);
+
+      res.AppendElement(
+          EventExtraEntry{"seq"_ns, IntToCString(threadIdAndSequence)});
+
+      sSequenceNumber.set(newSeqNum);
+
+      res.AppendElement(EventExtraEntry{"severity"_ns, severityString});
+
+      res.AppendElement(
+          EventExtraEntry{"source_file"_ns, nsCString(sourceFileRelativePath)});
+
+      res.AppendElement(
+          EventExtraEntry{"source_line"_ns, IntToCString(aSourceFileLine)});
+
+#    ifdef QM_ERROR_STACKS_ENABLED
+      if (!stackIdString.IsEmpty()) {
+        res.AppendElement(
+            EventExtraEntry{"stack_id"_ns, nsCString{stackIdString}});
+      }
+#    endif
+
+      return res;
+    }());
+
+    Telemetry::RecordEvent(Telemetry::EventID::DomQuotaTry_Error_Step,
+                           Nothing(), extra);
+  }
+#  endif
+}
+#endif
+
+#ifdef DEBUG
+Result<bool, nsresult> WarnIfFileIsUnknown(nsIFile& aFile,
+                                           const char* aSourceFilePath,
+                                           const int32_t aSourceFileLine) {
+  nsString leafName;
+  nsresult rv = aFile.GetLeafName(leafName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return Err(rv);
+  }
+
+  bool isDirectory;
+  rv = aFile.IsDirectory(&isDirectory);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return Err(rv);
+  }
+
+  if (!isDirectory) {
+    // Don't warn about OS metadata files. These files are only used in
+    // different platforms, but the profile can be shared across different
+    // operating systems, so we check it on all platforms.
+    if (leafName.Equals(kDSStoreFileName) ||
+        leafName.Equals(kDesktopFileName) ||
+        leafName.Equals(kDesktopIniFileName,
+                        nsCaseInsensitiveStringComparator) ||
+        leafName.Equals(kThumbsDbFileName, nsCaseInsensitiveStringComparator)) {
+      return false;
+    }
+
+    // Don't warn about files starting with ".".
+    if (leafName.First() == char16_t('.')) {
+      return false;
+    }
+  }
+
+  NS_DebugBreak(
+      NS_DEBUG_WARNING,
+      nsPrintfCString("Something (%s) in the directory that doesn't belong!",
+                      NS_ConvertUTF16toUTF8(leafName).get())
+          .get(),
+      nullptr, aSourceFilePath, aSourceFileLine);
+
+  return true;
+}
+#endif
+
+}  // namespace dom::quota
+}  // namespace mozilla
diff --git a/dom/quota/QuotaCommon.h b/dom/quota/QuotaCommon.h
new file mode 100644
index 0000000000..848118797e
--- /dev/null
+++ b/dom/quota/QuotaCommon.h
@@ -0,0 +1,1675 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_quotacommon_h__
+#define mozilla_dom_quota_quotacommon_h__
+
+#include "mozilla/dom/quota/Config.h"
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <type_traits>
+#include <utility>
+#include "mozIStorageStatement.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Likely.h"
+#include "mozilla/MacroArgs.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#if defined(QM_LOG_ERROR_ENABLED) && defined(QM_ERROR_STACKS_ENABLED)
+#  include "mozilla/Variant.h"
+#endif
+#include "mozilla/dom/QMResult.h"
+#include "mozilla/dom/quota/FirstInitializationAttemptsImpl.h"
+#include "mozilla/dom/quota/RemoveParen.h"
+#include "mozilla/dom/quota/ScopedLogExtraInfo.h"
+#include "mozilla/ipc/ProtocolUtils.h"
+#include "nsCOMPtr.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsIDirectoryEnumerator.h"
+#include "nsIEventTarget.h"
+#include "nsIFile.h"
+#include "nsLiteralString.h"
+#include "nsPrintfCString.h"
+#include "nsReadableUtils.h"
+#include "nsString.h"
+#include "nsTArray.h"
+#include "nsTLiteralString.h"
+
+namespace mozilla {
+template <typename T>
+class NotNull;
+}
+
+#define MOZ_ARGS_AFTER_3(a1, a2, a3, ...) __VA_ARGS__
+
+#define MOZ_ADD_ARGS2(...) , ##__VA_ARGS__
+#define MOZ_ADD_ARGS(...) MOZ_ADD_ARGS2(__VA_ARGS__)
+
+// Proper use of unique variable names can be tricky (especially if nesting of
+// the final macro is required).
+// See https://lifecs.likai.org/2016/07/c-preprocessor-hygienic-macros.html
+#define MOZ_UNIQUE_VAR(base) MOZ_CONCAT(base, __COUNTER__)
+
+// See https://florianjw.de/en/passing_overloaded_functions.html
+// TODO: Add a test for this macro.
+#define MOZ_SELECT_OVERLOAD(func)                         \
+  [](auto&&... aArgs) -> decltype(auto) {                 \
+    return func(std::forward<decltype(aArgs)>(aArgs)...); \
+  }
+
+#define DSSTORE_FILE_NAME ".DS_Store"
+#define DESKTOP_FILE_NAME ".desktop"
+#define DESKTOP_INI_FILE_NAME "desktop.ini"
+#define THUMBS_DB_FILE_NAME "thumbs.db"
+
+#define QM_WARNING(...)                                                      \
+  do {                                                                       \
+    nsPrintfCString str(__VA_ARGS__);                                        \
+    mozilla::dom::quota::ReportInternalError(__FILE__, __LINE__, str.get()); \
+    NS_WARNING(str.get());                                                   \
+  } while (0)
+
+#define QM_LOG_TEST() MOZ_LOG_TEST(GetQuotaManagerLogger(), LogLevel::Info)
+#define QM_LOG(_args) MOZ_LOG(GetQuotaManagerLogger(), LogLevel::Info, _args)
+
+#define UNKNOWN_FILE_WARNING(_leafName)                                       \
+  NS_WARNING(                                                                 \
+      nsPrintfCString("Something (%s) in the directory that doesn't belong!", \
+                      NS_ConvertUTF16toUTF8(_leafName).get())                 \
+          .get())
+
+// This macro should be used in directory traversals for files or directories
+// that are unknown for given directory traversal. It should only be called
+// after all known (directory traversal specific) files or directories have
+// been checked and handled.
+// XXX Consider renaming the macro to QM_LOG_UNKNOWN_DIR_ENTRY.
+#ifdef DEBUG
+#  define WARN_IF_FILE_IS_UNKNOWN(_file) \
+    mozilla::dom::quota::WarnIfFileIsUnknown(_file, __FILE__, __LINE__)
+#else
+#  define WARN_IF_FILE_IS_UNKNOWN(_file) Result<bool, nsresult>(false)
+#endif
+
+/**
+ * There are multiple ways to handle unrecoverable conditions (note that the
+ * patterns are put in reverse chronological order and only the first pattern
+ * QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT/QM_TRY_RETURN/QM_FAIL should be used in
+ * new code):
+ *
+ * 1. Using QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT/QM_TRY_RETURN/QM_FAIL macros
+ *    (Quota manager specific, defined below)
+ *
+ * Typical use cases:
+ *
+ * nsresult MyFunc1(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(aFile.Exists(&exists));
+ *   QM_TRY(OkIf(exists), NS_ERROR_FAILURE);
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc2(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(aFile.Exists(&exists), NS_ERROR_UNEXPECTED);
+ *   QM_TRY(OkIf(exists), NS_ERROR_UNEXPECTED);
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * void MyFunc3(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(aFile.Exists(&exists), QM_VOID);
+ *   QM_TRY(OkIf(exists), QM_VOID);
+ *
+ *   // The file exists, and data could be read from it here.
+ * }
+ *
+ * nsresult MyFunc4(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(storageFile->Exists(&exists), QM_PROPAGATE,
+ *          []() { NS_WARNING("The Exists call failed!"); });
+ *   QM_TRY(OkIf(exists), NS_ERROR_FAILURE,
+ *          []() { NS_WARNING("The file doesn't exist!"); });
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc5(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(aFile.Exists(&exists));
+ *   if (exists) {
+ *     // The file exists, and data could be read from it here.
+ *   } else {
+ *     QM_FAIL(NS_ERROR_FAILURE);
+ *   }
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc6(nsIFile& aFile) {
+ *   bool exists;
+ *   QM_TRY(aFile.Exists(&exists));
+ *   if (exists) {
+ *     // The file exists, and data could be read from it here.
+ *   } else {
+ *     QM_FAIL(NS_ERROR_FAILURE,
+ *             []() { NS_WARNING("The file doesn't exist!"); });
+ *   }
+ *
+ *   return NS_OK;
+ * }
+ *
+ * 2. Using MOZ_TRY/MOZ_TRY_VAR macros
+ *
+ * Typical use cases:
+ *
+ * nsresult MyFunc1(nsIFile& aFile) {
+ *   // MOZ_TRY can't return a custom return value
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc2(nsIFile& aFile) {
+ *   // MOZ_TRY can't return a custom return value
+ *
+ *   return NS_OK;
+ * }
+ *
+ * void MyFunc3(nsIFile& aFile) {
+ *   // MOZ_TRY can't return a custom return value, "void" in this case
+ * }
+ *
+ * nsresult MyFunc4(nsIFile& aFile) {
+ *   // MOZ_TRY can't return a custom return value and run an additional
+ *   // cleanup function
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc5(nsIFile& aFile) {
+ *   // There's no MOZ_FAIL, MOZ_TRY can't return a custom return value
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc6(nsIFile& aFile) {
+ *   // There's no MOZ_FAIL, MOZ_TRY can't return a custom return value and run
+ *   // an additional cleanup function
+ *
+ *   return NS_OK;
+ * }
+ *
+ * 3. Using NS_WARN_IF and NS_WARNING macro with own control flow handling
+ *
+ * Typical use cases:
+ *
+ * nsresult MyFunc1(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     return rv;
+ *   }
+ *   if (NS_WARN_IF(!exists) {
+ *     return NS_ERROR_FAILURE;
+ *   }
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc2(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     return NS_ERROR_UNEXPECTED;
+ *   }
+ *   if (NS_WARN_IF(!exists) {
+ *     return NS_ERROR_UNEXPECTED;
+ *   }
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * void MyFunc3(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     return;
+ *   }
+ *   if (NS_WARN_IF(!exists) {
+ *     return;
+ *   }
+ *
+ *   // The file exists, and data could be read from it here.
+ * }
+ *
+ * nsresult MyFunc4(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     NS_WARNING("The Exists call failed!");
+ *     return rv;
+ *   }
+ *   if (NS_WARN_IF(!exists) {
+ *     NS_WARNING("The file doesn't exist!");
+ *     return NS_ERROR_FAILURE;
+ *   }
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc5(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     return rv;
+ *   }
+ *   if (exists) {
+ *     // The file exists, and data could be read from it here.
+ *   } else {
+ *     return NS_ERROR_FAILURE;
+ *   }
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc6(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   if (NS_WARN_IF(NS_FAILED(rv)) {
+ *     return rv;
+ *   }
+ *   if (exists) {
+ *     // The file exists, and data could be read from it here.
+ *   } else {
+ *     NS_WARNING("The file doesn't exist!");
+ *     return NS_ERROR_FAILURE;
+ *   }
+ *
+ *   return NS_OK;
+ * }
+ *
+ * 4. Using NS_ENSURE_* macros
+ *
+ * Mainly:
+ * - NS_ENSURE_SUCCESS
+ * - NS_ENSURE_SUCCESS_VOID
+ * - NS_ENSURE_TRUE
+ * - NS_ENSURE_TRUE_VOID
+ *
+ * Typical use cases:
+ *
+ * nsresult MyFunc1(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   NS_ENSURE_SUCCESS(rv, rv);
+ *   NS_ENSURE_TRUE(exists, NS_ERROR_FAILURE);
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc2(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   NS_ENSURE_SUCCESS(rv, NS_ERROR_UNEXPECTED);
+ *   NS_ENSURE_TRUE(exists, NS_ERROR_UNEXPECTED);
+ *
+ *   // The file exists, and data could be read from it here.
+ *
+ *   return NS_OK;
+ * }
+ *
+ * void MyFunc3(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   NS_ENSURE_SUCCESS_VOID(rv);
+ *   NS_ENSURE_TRUE_VOID(exists);
+ *
+ *   // The file exists, and data could be read from it here.
+ * }
+ *
+ * nsresult MyFunc4(nsIFile& aFile) {
+ *   // NS_ENSURE_SUCCESS/NS_ENSURE_TRUE can't run an additional cleanup
+ *   // function
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc5(nsIFile& aFile) {
+ *   bool exists;
+ *   nsresult rv = aFile.Exists(&exists);
+ *   NS_ENSURE_SUCCESS(rv, rv);
+ *   if (exists) {
+ *     // The file exists, and data could be read from it here.
+ *   } else {
+ *     NS_ENSURE_TRUE(false, NS_ERROR_FAILURE);
+ *   }
+ *
+ *   return NS_OK;
+ * }
+ *
+ * nsresult MyFunc6(nsIFile& aFile) {
+ *   // NS_ENSURE_TRUE can't run an additional cleanup function
+ *
+ *   return NS_OK;
+ * }
+ *
+ * QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT is like MOZ_TRY/MOZ_TRY_VAR but if an
+ * error occurs it additionally calls a generic function HandleError to handle
+ * the error and it can be used to return custom return values as well and even
+ * call an additional cleanup function.
+ * HandleError currently only warns in debug builds, it will report to the
+ * browser console and telemetry in the future.
+ * The other advantage of QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT is that a local
+ * nsresult is not needed at all in all cases, all calls can be wrapped
+ * directly. If an error occurs, the warning contains a concrete call instead
+ * of the rv local variable. For example:
+ *
+ * 1. WARNING: NS_ENSURE_SUCCESS(rv, rv) failed with result 0x80004005
+ * (NS_ERROR_FAILURE): file XYZ, line N
+ *
+ * 2. WARNING: 'NS_FAILED(rv)', file XYZ, line N
+ *
+ * 3. Nothing (MOZ_TRY doesn't warn)
+ *
+ * 4. WARNING: Error: 'aFile.Exists(&exists)', file XYZ, line N
+ *
+ * QM_TRY_RETURN is a supplementary macro for cases when the result's success
+ * value can be directly returned (instead of assigning to a variable as in the
+ * QM_TRY_UNWRAP/QM_TRY_INSPECT case).
+ *
+ * QM_FAIL is a supplementary macro for cases when an error needs to be
+ * returned without evaluating an expression. It's possible to write
+ * QM_TRY(OkIf(false), NS_ERROR_FAILURE), but QM_FAIL(NS_ERROR_FAILURE) looks
+ * more straightforward.
+ *
+ * It's highly recommended to use
+ * QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT/QM_TRY_RETURN/QM_FAIL in new code for
+ * quota manager and quota clients. Existing code should be incrementally
+ * converted as needed.
+ *
+ * QM_TRY_VOID/QM_TRY_UNWRAP_VOID/QM_TRY_INSPECT_VOID/QM_FAIL_VOID is not
+ * defined on purpose since it's possible to use
+ * QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT/QM_FAIL even in void functions.
+ * However, QM_TRY(Task(), ) would look odd so it's recommended to use a dummy
+ * define QM_VOID that evaluates to nothing instead: QM_TRY(Task(), QM_VOID)
+ *
+ * Custom return values can be static or dynamically generated using functions
+ * with one of these signatures:
+ *   auto(const char* aFunc, const char* aExpr);
+ *   auto(const char* aFunc, const T& aRv);
+ *   auto(const T& aRc);
+ */
+
+#define QM_VOID
+
+#define QM_PROPAGATE Err(tryTempError)
+
+#define QM_IPC_FAIL(actor)                                                  \
+  [&_actor = *actor](const char* aFunc, const char* aExpr) {                \
+    return Err(                                                             \
+        mozilla::ipc::IPCResult::Fail(WrapNotNull(&_actor), aFunc, aExpr)); \
+  }
+
+#ifdef DEBUG
+#  define QM_ASSERT_UNREACHABLE                                               \
+    [](const char*, const char*) -> ::mozilla::GenericErrorResult<nsresult> { \
+      MOZ_CRASH("Should never be reached.");                                  \
+    }
+
+#  define QM_ASSERT_UNREACHABLE_VOID \
+    [](const char*, const char*) { MOZ_CRASH("Should never be reached."); }
+#endif
+
+#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
+#  define QM_DIAGNOSTIC_ASSERT_UNREACHABLE                                    \
+    [](const char*, const char*) -> ::mozilla::GenericErrorResult<nsresult> { \
+      MOZ_CRASH("Should never be reached.");                                  \
+    }
+
+#  define QM_DIAGNOSTIC_ASSERT_UNREACHABLE_VOID \
+    [](const char*, const char*) { MOZ_CRASH("Should never be reached."); }
+#endif
+
+// QM_MISSING_ARGS and QM_HANDLE_ERROR macros are implementation details of
+// QM_TRY/QM_TRY_UNWRAP/QM_TRY_INSPECT/QM_FAIL and shouldn't be used directly.
+
+#define QM_MISSING_ARGS(...)                           \
+  do {                                                 \
+    static_assert(false, "Did you forget arguments?"); \
+  } while (0)
+
+#ifdef DEBUG
+#  define QM_HANDLE_ERROR(expr, error, severity) \
+    HandleError(#expr, error, __FILE__, __LINE__, severity)
+#else
+#  define QM_HANDLE_ERROR(expr, error, severity) \
+    HandleError("Unavailable", error, __FILE__, __LINE__, severity)
+#endif
+
+#ifdef DEBUG
+#  define QM_HANDLE_ERROR_RETURN_NOTHING(expr, error, severity) \
+    HandleErrorReturnNothing(#expr, error, __FILE__, __LINE__, severity)
+#else
+#  define QM_HANDLE_ERROR_RETURN_NOTHING(expr, error, severity) \
+    HandleErrorReturnNothing("Unavailable", error, __FILE__, __LINE__, severity)
+#endif
+
+#ifdef DEBUG
+#  define QM_HANDLE_ERROR_WITH_CLEANUP_RETURN_NOTHING(expr, error, severity, \
+                                                      cleanup)               \
+    HandleErrorWithCleanupReturnNothing(#expr, error, __FILE__, __LINE__,    \
+                                        severity, cleanup)
+#else
+#  define QM_HANDLE_ERROR_WITH_CLEANUP_RETURN_NOTHING(expr, error, severity, \
+                                                      cleanup)               \
+    HandleErrorWithCleanupReturnNothing("Unavailable", error, __FILE__,      \
+                                        __LINE__, severity, cleanup)
+#endif
+
+// Handles the case when QM_VOID is passed as a custom return value.
+#define QM_HANDLE_CUSTOM_RET_VAL_HELPER0(func, expr, error)
+
+#define QM_HANDLE_CUSTOM_RET_VAL_HELPER1(func, expr, error, customRetVal) \
+  mozilla::dom::quota::HandleCustomRetVal(func, #expr, error, customRetVal)
+
+#define QM_HANDLE_CUSTOM_RET_VAL_GLUE(a, b) a b
+
+#define QM_HANDLE_CUSTOM_RET_VAL(...)                                 \
+  QM_HANDLE_CUSTOM_RET_VAL_GLUE(                                      \
+      MOZ_PASTE_PREFIX_AND_ARG_COUNT(QM_HANDLE_CUSTOM_RET_VAL_HELPER, \
+                                     MOZ_ARGS_AFTER_3(__VA_ARGS__)),  \
+      (MOZ_ARG_1(__VA_ARGS__), MOZ_ARG_2(__VA_ARGS__),                \
+       MOZ_ARG_3(__VA_ARGS__) MOZ_ADD_ARGS(MOZ_ARGS_AFTER_3(__VA_ARGS__))))
+
+// QM_TRY_PROPAGATE_ERR, QM_TRY_CUSTOM_RET_VAL,
+// QM_TRY_CUSTOM_RET_VAL_WITH_CLEANUP and QM_TRY_GLUE macros are implementation
+// details of QM_TRY and shouldn't be used directly.
+
+// Handles the two arguments case when the error is propagated.
+#define QM_TRY_PROPAGATE_ERR(tryResult, expr)                                \
+  auto tryResult = (expr);                                                   \
+  static_assert(std::is_empty_v<typename decltype(tryResult)::ok_type>);     \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryResult.inspectErr(), mozilla::dom::quota::Severity::Error); \
+    return tryResult.propagateErr();                                         \
+  }
+
+// Handles the three arguments case when a custom return value needs to be
+// returned
+#define QM_TRY_CUSTOM_RET_VAL(tryResult, expr, customRetVal)                 \
+  auto tryResult = (expr);                                                   \
+  static_assert(std::is_empty_v<typename decltype(tryResult)::ok_type>);     \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    auto tryTempError MOZ_MAYBE_UNUSED = tryResult.unwrapErr();              \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryTempError, mozilla::dom::quota::Severity::Error);           \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                  \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal); \
+  }
+
+// Handles the four arguments case when a cleanup function needs to be called
+// before a custom return value is returned
+#define QM_TRY_CUSTOM_RET_VAL_WITH_CLEANUP(tryResult, expr, customRetVal,    \
+                                           cleanup)                          \
+  auto tryResult = (expr);                                                   \
+  static_assert(std::is_empty_v<typename decltype(tryResult)::ok_type>);     \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    auto tryTempError = tryResult.unwrapErr();                               \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryTempError, mozilla::dom::quota::Severity::Error);           \
+    cleanup(tryTempError);                                                   \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                  \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal); \
+  }
+
+// Chooses the final implementation macro for given argument count.
+// This could use MOZ_PASTE_PREFIX_AND_ARG_COUNT, but explicit named suffxes
+// read slightly better than plain numbers.
+// See also
+// https://stackoverflow.com/questions/3046889/optional-parameters-with-c-macros
+#define QM_TRY_META(...)                                                       \
+  {                                                                            \
+    MOZ_ARG_6(                                                                 \
+        , ##__VA_ARGS__, QM_TRY_CUSTOM_RET_VAL_WITH_CLEANUP(__VA_ARGS__),      \
+        QM_TRY_CUSTOM_RET_VAL(__VA_ARGS__), QM_TRY_PROPAGATE_ERR(__VA_ARGS__), \
+        QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__))            \
+  }
+
+// Generates unique variable name. This extra internal macro (along with
+// __COUNTER__) allows nesting of the final macro.
+#define QM_TRY_GLUE(...) QM_TRY_META(MOZ_UNIQUE_VAR(tryResult), ##__VA_ARGS__)
+
+/**
+ * QM_TRY(expr[, customRetVal, cleanup]) is the C++ equivalent of Rust's
+ * `try!(expr);`. First, it evaluates expr, which must produce a Result value
+ * with empty ok_type. On Success, it does nothing else. On error, it calls
+ * HandleError and an additional cleanup function (if the third argument was
+ * passed) and finally returns an error Result from the enclosing function or a
+ * custom return value (if the second argument was passed).
+ */
+#define QM_TRY(...) QM_TRY_GLUE(__VA_ARGS__)
+
+// QM_TRY_ASSIGN_PROPAGATE_ERR, QM_TRY_ASSIGN_CUSTOM_RET_VAL,
+// QM_TRY_ASSIGN_CUSTOM_RET_VAL_WITH_CLEANUP and QM_TRY_ASSIGN_GLUE macros are
+// implementation details of QM_TRY_UNWRAP/QM_TRY_INSPECT and shouldn't be used
+// directly.
+
+// Handles the four arguments case when the error is propagated.
+#define QM_TRY_ASSIGN_PROPAGATE_ERR(tryResult, accessFunction, target, expr) \
+  auto tryResult = (expr);                                                   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryResult.inspectErr(), mozilla::dom::quota::Severity::Error); \
+    return tryResult.propagateErr();                                         \
+  }                                                                          \
+  MOZ_REMOVE_PAREN(target) = tryResult.accessFunction();
+
+// Handles the five arguments case when a custom return value needs to be
+// returned
+#define QM_TRY_ASSIGN_CUSTOM_RET_VAL(tryResult, accessFunction, target, expr, \
+                                     customRetVal)                            \
+  auto tryResult = (expr);                                                    \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                      \
+    auto tryTempError MOZ_MAYBE_UNUSED = tryResult.unwrapErr();               \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                     \
+        expr, tryTempError, mozilla::dom::quota::Severity::Error);            \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                   \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal);  \
+  }                                                                           \
+  MOZ_REMOVE_PAREN(target) = tryResult.accessFunction();
+
+// Handles the six arguments case when a cleanup function needs to be called
+// before a custom return value is returned
+#define QM_TRY_ASSIGN_CUSTOM_RET_VAL_WITH_CLEANUP(                           \
+    tryResult, accessFunction, target, expr, customRetVal, cleanup)          \
+  auto tryResult = (expr);                                                   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    auto tryTempError = tryResult.unwrapErr();                               \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryTempError, mozilla::dom::quota::Severity::Error);           \
+    cleanup(tryTempError);                                                   \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                  \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal); \
+  }                                                                          \
+  MOZ_REMOVE_PAREN(target) = tryResult.accessFunction();
+
+// Chooses the final implementation macro for given argument count.
+// See also the comment for QM_TRY_META.
+#define QM_TRY_ASSIGN_META(...)                                         \
+  MOZ_ARG_8(, ##__VA_ARGS__,                                            \
+            QM_TRY_ASSIGN_CUSTOM_RET_VAL_WITH_CLEANUP(__VA_ARGS__),     \
+            QM_TRY_ASSIGN_CUSTOM_RET_VAL(__VA_ARGS__),                  \
+            QM_TRY_ASSIGN_PROPAGATE_ERR(__VA_ARGS__),                   \
+            QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__), \
+            QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__))
+
+// Generates unique variable name. This extra internal macro (along with
+// __COUNTER__) allows nesting of the final macro.
+#define QM_TRY_ASSIGN_GLUE(accessFunction, ...) \
+  QM_TRY_ASSIGN_META(MOZ_UNIQUE_VAR(tryResult), accessFunction, ##__VA_ARGS__)
+
+/**
+ * QM_TRY_UNWRAP(target, expr[, customRetVal, cleanup]) is the C++ equivalent of
+ * Rust's `target = try!(expr);`. First, it evaluates expr, which must produce
+ * a Result value. On success, the result's success value is unwrapped and
+ * assigned to target. On error, it calls HandleError and an additional cleanup
+ * function (if the fourth argument was passed) and finally returns the error
+ * result or a custom return value (if the third argument was passed). |target|
+ * must be an lvalue.
+ */
+#define QM_TRY_UNWRAP(...) QM_TRY_ASSIGN_GLUE(unwrap, __VA_ARGS__)
+
+/**
+ * QM_TRY_INSPECT is similar to QM_TRY_UNWRAP, but it does not unwrap a success
+ * value, but inspects it and binds it to the target. It can therefore only be
+ * used when the target declares a const&. In general,
+ *
+ *   QM_TRY_INSPECT(const auto &target, DoSomething())
+ *
+ * should be preferred over
+ *
+ *   QM_TRY_UNWRAP(const auto target, DoSomething())
+ *
+ * as it avoids unnecessary moves/copies.
+ */
+#define QM_TRY_INSPECT(...) QM_TRY_ASSIGN_GLUE(inspect, __VA_ARGS__)
+
+// QM_TRY_RETURN_PROPAGATE_ERR, QM_TRY_RETURN_CUSTOM_RET_VAL,
+// QM_TRY_RETURN_CUSTOM_RET_VAL_WITH_CLEANUP and QM_TRY_RETURN_GLUE macros are
+// implementation details of QM_TRY_RETURN and shouldn't be used directly.
+
+// Handles the two arguments case when the error is (also) propagated.
+// Note that this deliberately uses a single return statement without going
+// through unwrap/unwrapErr/propagateErr, so that this does not prevent NRVO or
+// tail call optimizations when possible.
+#define QM_TRY_RETURN_PROPAGATE_ERR(tryResult, expr)                         \
+  auto tryResult = (expr);                                                   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryResult.inspectErr(), mozilla::dom::quota::Severity::Error); \
+  }                                                                          \
+  return tryResult;
+
+// Handles the three arguments case when a custom return value needs to be
+// returned
+#define QM_TRY_RETURN_CUSTOM_RET_VAL(tryResult, expr, customRetVal)          \
+  auto tryResult = (expr);                                                   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    auto tryTempError MOZ_MAYBE_UNUSED = tryResult.unwrapErr();              \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryResult.inspectErr(), mozilla::dom::quota::Severity::Error); \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                  \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal); \
+  }                                                                          \
+  return tryResult.unwrap();
+
+// Handles the four arguments case when a cleanup function needs to be called
+// before a custom return value is returned
+#define QM_TRY_RETURN_CUSTOM_RET_VAL_WITH_CLEANUP(tryResult, expr,           \
+                                                  customRetVal, cleanup)     \
+  auto tryResult = (expr);                                                   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                     \
+    auto tryTempError = tryResult.unwrapErr();                               \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                    \
+        expr, tryTempError, mozilla::dom::quota::Severity::Error);           \
+    cleanup(tryTempError);                                                   \
+    constexpr const auto& func MOZ_MAYBE_UNUSED = __func__;                  \
+    return QM_HANDLE_CUSTOM_RET_VAL(func, expr, tryTempError, customRetVal); \
+  }                                                                          \
+  return tryResult.unwrap();
+
+// Chooses the final implementation macro for given argument count.
+// See also the comment for QM_TRY_META.
+#define QM_TRY_RETURN_META(...)                                           \
+  {                                                                       \
+    MOZ_ARG_6(, ##__VA_ARGS__,                                            \
+              QM_TRY_RETURN_CUSTOM_RET_VAL_WITH_CLEANUP(__VA_ARGS__),     \
+              QM_TRY_RETURN_CUSTOM_RET_VAL(__VA_ARGS__),                  \
+              QM_TRY_RETURN_PROPAGATE_ERR(__VA_ARGS__),                   \
+              QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__)) \
+  }
+
+// Generates unique variable name. This extra internal macro (along with
+// __COUNTER__) allows nesting of the final macro.
+#define QM_TRY_RETURN_GLUE(...) \
+  QM_TRY_RETURN_META(MOZ_UNIQUE_VAR(tryResult), ##__VA_ARGS__)
+
+/**
+ * QM_TRY_RETURN(expr[, customRetVal, cleanup]) evaluates expr, which must
+ * produce a Result value. On success, the result's success value is returned.
+ * On error, it calls HandleError and an additional cleanup function (if the
+ * third argument was passed) and finally returns the error result or a custom
+ * return value (if the second argument was passed).
+ */
+#define QM_TRY_RETURN(...) QM_TRY_RETURN_GLUE(__VA_ARGS__)
+
+// QM_FAIL_RET_VAL and QM_FAIL_RET_VAL_WITH_CLEANUP macros are implementation
+// details of QM_FAIL and shouldn't be used directly.
+
+// Handles the one argument case when just an error is returned
+#define QM_FAIL_RET_VAL(retVal)                                               \
+  mozilla::dom::quota::QM_HANDLE_ERROR(Failure, 0,                            \
+                                       mozilla::dom::quota::Severity::Error); \
+  return retVal;
+
+// Handles the two arguments case when a cleanup function needs to be called
+// before a return value is returned
+#define QM_FAIL_RET_VAL_WITH_CLEANUP(retVal, cleanup)                         \
+  mozilla::dom::quota::QM_HANDLE_ERROR(Failure, 0,                            \
+                                       mozilla::dom::quota::Severity::Error); \
+  cleanup();                                                                  \
+  return retVal;
+
+// Chooses the final implementation macro for given argument count.
+// See also the comment for QM_TRY_META.
+#define QM_FAIL_META(...)                                               \
+  MOZ_ARG_4(, ##__VA_ARGS__, QM_FAIL_RET_VAL_WITH_CLEANUP(__VA_ARGS__), \
+            QM_FAIL_RET_VAL(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__))
+
+// This extra internal macro allows nesting of the final macro.
+#define QM_FAIL_GLUE(...) QM_FAIL_META(__VA_ARGS__)
+
+/**
+ * QM_FAIL(retVal[, cleanup]) calls HandleError and an additional cleanup
+ * function (if the second argument was passed) and returns a return value.
+ */
+#define QM_FAIL(...) QM_FAIL_GLUE(__VA_ARGS__)
+
+// QM_REPORTONLY_TRY, QM_REPORTONLY_TRY_WITH_CLEANUP, QM_REPORTONLY_TRY_GLUE
+// macros are implementation details of QM_WARNONLY_TRY/QM_INFOONLY_TRY and
+// shouldn't be used directly.
+
+// Handles the three arguments case when only a warning/info is reported.
+#define QM_REPORTONLY_TRY(tryResult, severity, expr)                           \
+  auto tryResult = (expr);                                                     \
+  static_assert(std::is_empty_v<typename decltype(tryResult)::ok_type>);       \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                       \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                      \
+        expr, tryResult.unwrapErr(), mozilla::dom::quota::Severity::severity); \
+  }
+
+// Handles the four arguments case when a cleanup function needs to be called
+#define QM_REPORTONLY_TRY_WITH_CLEANUP(tryResult, severity, expr, cleanup) \
+  auto tryResult = (expr);                                                 \
+  static_assert(std::is_empty_v<typename decltype(tryResult)::ok_type>);   \
+  if (MOZ_UNLIKELY(tryResult.isErr())) {                                   \
+    auto tryTempError = tryResult.unwrapErr();                             \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                                  \
+        expr, tryTempError, mozilla::dom::quota::Severity::severity);      \
+    cleanup(tryTempError);                                                 \
+  }
+
+// Chooses the final implementation macro for given argument count.
+// See also the comment for QM_TRY_META.
+#define QM_REPORTONLY_TRY_META(...)                                         \
+  {                                                                         \
+    MOZ_ARG_6(, ##__VA_ARGS__, QM_REPORTONLY_TRY_WITH_CLEANUP(__VA_ARGS__), \
+              QM_REPORTONLY_TRY(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__), \
+              QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__))   \
+  }
+
+// Generates unique variable name. This extra internal macro (along with
+// __COUNTER__) allows nesting of the final macro.
+#define QM_REPORTONLY_TRY_GLUE(severity, ...) \
+  QM_REPORTONLY_TRY_META(MOZ_UNIQUE_VAR(tryResult), severity, ##__VA_ARGS__)
+
+/**
+ * QM_WARNONLY_TRY(expr[, cleanup]) evaluates expr, which must produce a
+ * Result value with empty ok_type. On Success, it does nothing else. On error,
+ * it calls HandleError and an additional cleanup function (if the second
+ * argument was passed). This macro never returns and failures are always
+ * reported using a lower level of severity relative to failures reported by
+ * QM_TRY. The macro is intended for failures that should not be propagated.
+ */
+#define QM_WARNONLY_TRY(...) QM_REPORTONLY_TRY_GLUE(Warning, __VA_ARGS__)
+
+/**
+ * QM_INFOONLY_TRY is like QM_WARNONLY_TRY. The only difference is that
+ * failures are reported using a lower level of severity relative to failures
+ * reported by QM_WARNONLY_TRY.
+ */
+#define QM_INFOONLY_TRY(...) QM_REPORTONLY_TRY_GLUE(Info, __VA_ARGS__)
+
+// QM_REPORTONLY_TRY_ASSIGN, QM_REPORTONLY_TRY_ASSIGN_WITH_CLEANUP,
+// QM_REPORTONLY_TRY_ASSIGN_GLUE macros are implementation details of
+// QM_WARNONLY_TRY_UNWRAP/QM_INFOONLY_TRY_UNWRAP and shouldn't be used
+// directly.
+
+// Handles the four arguments case when only a warning/info is reported.
+#define QM_REPORTONLY_TRY_ASSIGN(tryResult, severity, target, expr) \
+  auto tryResult = (expr);                                          \
+  MOZ_REMOVE_PAREN(target) =                                        \
+      MOZ_LIKELY(tryResult.isOk())                                  \
+          ? Some(tryResult.unwrap())                                \
+          : mozilla::dom::quota::QM_HANDLE_ERROR_RETURN_NOTHING(    \
+                expr, tryResult.unwrapErr(),                        \
+                mozilla::dom::quota::Severity::severity);
+
+// Handles the five arguments case when a cleanup function needs to be called
+#define QM_REPORTONLY_TRY_ASSIGN_WITH_CLEANUP(tryResult, severity, target,    \
+                                              expr, cleanup)                  \
+  auto tryResult = (expr);                                                    \
+  MOZ_REMOVE_PAREN(target) =                                                  \
+      MOZ_LIKELY(tryResult.isOk())                                            \
+          ? Some(tryResult.unwrap())                                          \
+          : mozilla::dom::quota::QM_HANDLE_ERROR_WITH_CLEANUP_RETURN_NOTHING( \
+                expr, tryResult.unwrapErr(),                                  \
+                mozilla::dom::quota::Severity::severity, cleanup);
+
+// Chooses the final implementation macro for given argument count.
+// See also the comment for QM_TRY_META.
+#define QM_REPORTONLY_TRY_ASSIGN_META(...)                              \
+  MOZ_ARG_7(, ##__VA_ARGS__,                                            \
+            QM_REPORTONLY_TRY_ASSIGN_WITH_CLEANUP(__VA_ARGS__),         \
+            QM_REPORTONLY_TRY_ASSIGN(__VA_ARGS__),                      \
+            QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__), \
+            QM_MISSING_ARGS(__VA_ARGS__), QM_MISSING_ARGS(__VA_ARGS__))
+
+// Generates unique variable name. This extra internal macro (along with
+// __COUNTER__) allows nesting of the final macro.
+#define QM_REPORTONLY_TRY_ASSIGN_GLUE(severity, ...)                 \
+  QM_REPORTONLY_TRY_ASSIGN_META(MOZ_UNIQUE_VAR(tryResult), severity, \
+                                ##__VA_ARGS__)
+
+/**
+ * QM_WARNONLY_TRY_UNWRAP(target, expr[, cleanup]) evaluates expr, which must
+ * produce a Result value. On success, the result's success value is first
+ * unwrapped from the Result, then wrapped in a Maybe and finally assigned to
+ * target. On error, it calls HandleError and an additional cleanup
+ * function (if the third argument was passed) and finally assigns Nothing to
+ * target. |target| must be an lvalue. This macro never returns and failures
+ * are always reported using a lower level of severity relative to failures
+ * reported by QM_TRY_UNWRAP/QM_TRY_INSPECT. The macro is intended for failures
+ * that should not be propagated.
+ */
+#define QM_WARNONLY_TRY_UNWRAP(...) \
+  QM_REPORTONLY_TRY_ASSIGN_GLUE(Warning, __VA_ARGS__)
+
+// QM_WARNONLY_TRY_INSPECT doesn't make sense.
+
+/**
+ * QM_INFOONLY_TRY_UNWRAP is like QM_WARNONLY_TRY_UNWRAP. The only difference is
+ * that failures are reported using a lower level of severity relative to
+ * failures reported by QM_WARNONLY_TRY_UNWRAP.
+ */
+#define QM_INFOONLY_TRY_UNWRAP(...) \
+  QM_REPORTONLY_TRY_ASSIGN_GLUE(Info, __VA_ARGS__)
+
+// QM_INFOONLY_TRY_INSPECT doesn't make sense.
+
+// QM_OR_ELSE_REPORT macro is an implementation detail of
+// QM_OR_ELSE_WARN/QM_OR_ELSE_INFO/QM_OR_ELSE_LOG_VERBOSE and shouldn't be used
+// directly.
+
+#define QM_OR_ELSE_REPORT(severity, expr, fallback)                \
+  (expr).orElse([&](const auto& firstRes) {                        \
+    mozilla::dom::quota::QM_HANDLE_ERROR(                          \
+        #expr, firstRes, mozilla::dom::quota::Severity::severity); \
+    return fallback(firstRes);                                     \
+  })
+
+/*
+ * QM_OR_ELSE_WARN(expr, fallback) evaluates expr, which must produce a Result
+ * value. On Success, it just moves the success over. On error, it calls
+ * HandleError (with the Warning severity) and a fallback function (passed as
+ * the second argument) which produces a new result. Failed expr is always
+ * reported as a warning (the macro essentially wraps the fallback function
+ * with a warning). QM_OR_ELSE_WARN is a sub macro and is intended to be used
+ * along with one of the main macros such as QM_TRY.
+ */
+#define QM_OR_ELSE_WARN(...) QM_OR_ELSE_REPORT(Warning, __VA_ARGS__)
+
+/**
+ * QM_OR_ELSE_INFO is like QM_OR_ELSE_WARN. The only difference is that
+ * failures are reported using a lower level of severity relative to failures
+ * reported by QM_OR_ELSE_WARN.
+ */
+#define QM_OR_ELSE_INFO(...) QM_OR_ELSE_REPORT(Info, __VA_ARGS__)
+
+/**
+ * QM_OR_ELSE_LOG_VERBOSE is like QM_OR_ELSE_WARN. The only difference is that
+ * failures are reported using the lowest severity which is currently ignored
+ * in LogError, so nothing goes to the console, browser console and telemetry.
+ * Since nothing goes to the telemetry, the macro can't signal the end of the
+ * underlying error stack or change the type of the error stack in the
+ * telemetry. For that reason, the expression shouldn't contain nested QM_TRY
+ * macro uses.
+ */
+#define QM_OR_ELSE_LOG_VERBOSE(...) QM_OR_ELSE_REPORT(Log, __VA_ARGS__)
+
+namespace mozilla::dom::quota {
+
+// XXX Support orElseIf directly in mozilla::Result
+template <typename V, typename E, typename P, typename F>
+auto OrElseIf(Result<V, E>&& aResult, P&& aPred, F&& aFunc) -> Result<V, E> {
+  return MOZ_UNLIKELY(aResult.isErr())
+             ? (std::forward<P>(aPred)(aResult.inspectErr()))
+                   ? std::forward<F>(aFunc)(aResult.unwrapErr())
+                   : aResult.propagateErr()
+             : aResult.unwrap();
+}
+
+}  // namespace mozilla::dom::quota
+
+// QM_OR_ELSE_REPORT_IF macro is an implementation detail of
+// QM_OR_ELSE_WARN_IF/QM_OR_ELSE_INFO_IF/QM_OR_ELSE_LOG_VERBOSE_IF and
+// shouldn't be used directly.
+
+#define QM_OR_ELSE_REPORT_IF(severity, expr, predicate, fallback) \
+  mozilla::dom::quota::OrElseIf(                                  \
+      (expr),                                                     \
+      [&](const auto& firstRes) {                                 \
+        bool res = predicate(firstRes);                           \
+        mozilla::dom::quota::QM_HANDLE_ERROR(                     \
+            #expr, firstRes,                                      \
+            res ? mozilla::dom::quota::Severity::severity         \
+                : mozilla::dom::quota::Severity::Error);          \
+        return res;                                               \
+      },                                                          \
+      fallback)
+
+/*
+ * QM_OR_ELSE_WARN_IF(expr, predicate, fallback) evaluates expr first, which
+ * must produce a Result value. On Success, it just moves the success over.
+ * On error, it calls a predicate function (passed as the second argument) and
+ * then it either calls HandleError (with the Warning severity) and a fallback
+ * function (passed as the third argument) which produces a new result if the
+ * predicate returned true. Or it calls HandleError (with the Error severity)
+ * and propagates the error result if the predicate returned false. So failed
+ * expr can be reported as a warning or as an error depending on the predicate.
+ * QM_OR_ELSE_WARN_IF is a sub macro and is intended to be used along with one
+ * of the main macros such as QM_TRY.
+ */
+#define QM_OR_ELSE_WARN_IF(...) QM_OR_ELSE_REPORT_IF(Warning, __VA_ARGS__)
+
+/**
+ * QM_OR_ELSE_INFO_IF is like QM_OR_ELSE_WARN_IF. The only difference is that
+ * failures are reported using a lower level of severity relative to failures
+ * reported by QM_OR_ELSE_WARN_IF.
+ */
+#define QM_OR_ELSE_INFO_IF(...) QM_OR_ELSE_REPORT_IF(Info, __VA_ARGS__)
+
+/**
+ * QM_OR_ELSE_LOG_VERBOSE_IF is like QM_OR_ELSE_WARN_IF. The only difference is
+ * that failures are reported using the lowest severity which is currently
+ * ignored in LogError, so nothing goes to the console, browser console and
+ * telemetry. Since nothing goes to the telemetry, the macro can't signal the
+ * end of the underlying error stack or change the type of the error stack in
+ * the telemetry. For that reason, the expression shouldn't contain nested
+ * QM_TRY macro uses.
+ */
+#define QM_OR_ELSE_LOG_VERBOSE_IF(...) \
+  QM_OR_ELSE_REPORT_IF(Verbose, __VA_ARGS__)
+
+// Telemetry probes to collect number of failure during the initialization.
+#ifdef NIGHTLY_BUILD
+#  define RECORD_IN_NIGHTLY(_recorder, _status) \
+    do {                                        \
+      if (NS_SUCCEEDED(_recorder)) {            \
+        _recorder = _status;                    \
+      }                                         \
+    } while (0)
+
+#  define OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS \
+    Ok {}
+
+#  define RETURN_STATUS_OR_RESULT(_status, _rv) \
+    return Err(NS_FAILED(_status) ? (_status) : (_rv))
+#else
+#  define RECORD_IN_NIGHTLY(_dummy, _status) \
+    {}
+
+#  define OK_IN_NIGHTLY_PROPAGATE_IN_OTHERS QM_PROPAGATE
+
+#  define RETURN_STATUS_OR_RESULT(_status, _rv) return Err(_rv)
+#endif
+
+class mozIStorageConnection;
+class mozIStorageStatement;
+class nsIFile;
+
+namespace mozilla {
+
+class LogModule;
+
+struct CreateIfNonExistent {};
+
+struct NotOk {};
+
+// Allow MOZ_TRY/QM_TRY to handle `bool` values by wrapping them with OkIf.
+// TODO: Maybe move this to mfbt/ResultExtensions.h
+inline Result<Ok, NotOk> OkIf(bool aValue) {
+  if (aValue) {
+    return Ok();
+  }
+  return Err(NotOk());
+}
+
+// TODO: Maybe move this to mfbt/ResultExtensions.h
+template <auto SuccessValue>
+auto OkToOk(Ok) -> Result<decltype(SuccessValue), nsresult> {
+  return SuccessValue;
+}
+
+template <nsresult ErrorValue, auto SuccessValue,
+          typename V = decltype(SuccessValue)>
+auto ErrToOkOrErr(nsresult aValue) -> Result<V, nsresult> {
+  if (aValue == ErrorValue) {
+    return V{SuccessValue};
+  }
+  return Err(aValue);
+}
+
+template <nsresult ErrorValue, typename V = mozilla::Ok>
+auto ErrToDefaultOkOrErr(nsresult aValue) -> Result<V, nsresult> {
+  if (aValue == ErrorValue) {
+    return V{};
+  }
+  return Err(aValue);
+}
+
+// Helper template function so that QM_TRY predicates checking for a specific
+// error can be concisely written as IsSpecificError<NS_SOME_ERROR> instead of
+// as a more verbose lambda.
+template <nsresult ErrorValue>
+bool IsSpecificError(const nsresult aValue) {
+  return aValue == ErrorValue;
+}
+
+// Helper template function so that QM_TRY fallback functions that are
+// converting errors into specific in-band success values can be concisely
+// written as ErrToOk<SuccessValueToReturn> (with the return type inferred).
+// For example, many file-related APIs that access information about a file may
+// return an nsresult error code if the file does not exist. From an
+// application perspective, the file not existing is not actually exceptional
+// and can instead be handled by the success case.
+template <auto SuccessValue, typename V = decltype(SuccessValue)>
+auto ErrToOk(const nsresult aValue) -> Result<V, nsresult> {
+  return V{SuccessValue};
+}
+
+// Helper template function so that QM_TRY fallback functions that are
+// suppressing errors by converting them into (generic) success can be
+// concisely written as ErrToDefaultOk<>.
+template <typename V = mozilla::Ok>
+auto ErrToDefaultOk(const nsresult aValue) -> Result<V, nsresult> {
+  return V{};
+}
+
+template <typename MozPromiseType, typename RejectValueT = nsresult>
+auto CreateAndRejectMozPromise(const char* aFunc, const RejectValueT& aRv)
+    -> decltype(auto) {
+  if constexpr (std::is_same_v<RejectValueT, nsresult>) {
+    return MozPromiseType::CreateAndReject(aRv, aFunc);
+  } else if constexpr (std::is_same_v<RejectValueT, QMResult>) {
+    return MozPromiseType::CreateAndReject(aRv.NSResult(), aFunc);
+  }
+}
+
+RefPtr<BoolPromise> CreateAndRejectBoolPromise(const char* aFunc, nsresult aRv);
+
+RefPtr<Int64Promise> CreateAndRejectInt64Promise(const char* aFunc,
+                                                 nsresult aRv);
+
+RefPtr<BoolPromise> CreateAndRejectBoolPromiseFromQMResult(const char* aFunc,
+                                                           const QMResult& aRv);
+
+// Like Rust's collect with a step function, not a generic iterator/range.
+//
+// Cond must be a function type with a return type to Result<V, E>, where
+// V is convertible to bool
+// - success converts to true indicates that collection shall continue
+// - success converts to false indicates that collection is completed
+// - error indicates that collection shall stop, propagating the error
+//
+// Body must a function type accepting a V xvalue with a return type convertible
+// to Result<empty, E>.
+template <typename Step, typename Body>
+auto CollectEach(Step aStep, const Body& aBody)
+    -> Result<mozilla::Ok, typename std::invoke_result_t<Step>::err_type> {
+  using StepResultType = typename std::invoke_result_t<Step>::ok_type;
+
+  static_assert(
+      std::is_empty_v<
+          typename std::invoke_result_t<Body, StepResultType&&>::ok_type>);
+
+  while (true) {
+    StepResultType element;
+    MOZ_TRY_VAR(element, aStep());
+
+    if (!static_cast<bool>(element)) {
+      break;
+    }
+
+    MOZ_TRY(aBody(std::move(element)));
+  }
+
+  return mozilla::Ok{};
+}
+
+// This is like std::reduce with a to-be-defined execution policy (we don't want
+// to std::terminate on an error, but probably it's fine to just propagate any
+// error that occurred), operating not on a pair of iterators but rather a
+// generator function.
+template <typename InputGenerator, typename T, typename BinaryOp>
+auto ReduceEach(InputGenerator aInputGenerator, T aInit,
+                const BinaryOp& aBinaryOp)
+    -> Result<T, typename std::invoke_result_t<InputGenerator>::err_type> {
+  T res = std::move(aInit);
+
+  // XXX This can be done in parallel!
+  MOZ_TRY(CollectEach(
+      std::move(aInputGenerator),
+      [&res, &aBinaryOp](const auto& element)
+          -> Result<Ok,
+                    typename std::invoke_result_t<InputGenerator>::err_type> {
+        MOZ_TRY_VAR(res, aBinaryOp(std::move(res), element));
+
+        return Ok{};
+      }));
+
+  return std::move(res);
+}
+
+// This is like std::reduce with a to-be-defined execution policy (we don't want
+// to std::terminate on an error, but probably it's fine to just propagate any
+// error that occurred).
+template <typename Range, typename T, typename BinaryOp>
+auto Reduce(Range&& aRange, T aInit, const BinaryOp& aBinaryOp) {
+  using std::begin;
+  using std::end;
+  return ReduceEach(
+      [it = begin(aRange), end = end(aRange)]() mutable {
+        auto res = ToMaybeRef(it != end ? &*it++ : nullptr);
+        return Result<decltype(res), typename std::invoke_result_t<
+                                         BinaryOp, T, decltype(res)>::err_type>(
+            res);
+      },
+      aInit, aBinaryOp);
+}
+
+template <typename Range, typename Body>
+auto CollectEachInRange(Range&& aRange, const Body& aBody)
+    -> Result<mozilla::Ok, nsresult> {
+  for (auto&& element : aRange) {
+    MOZ_TRY(aBody(element));
+  }
+
+  return mozilla::Ok{};
+}
+
+// Like Rust's collect with a while loop, not a generic iterator/range.
+//
+// Cond must be a function type accepting no parameters with a return type
+// convertible to Result<bool, E>, where
+// - success true indicates that collection shall continue
+// - success false indicates that collection is completed
+// - error indicates that collection shall stop, propagating the error
+//
+// Body must a function type accepting no parameters with a return type
+// convertible to Result<empty, E>.
+template <typename Cond, typename Body>
+auto CollectWhile(const Cond& aCond, const Body& aBody)
+    -> Result<mozilla::Ok, typename std::invoke_result_t<Cond>::err_type> {
+  return CollectEach(aCond, [&aBody](bool) { return aBody(); });
+}
+
+template <>
+class [[nodiscard]] GenericErrorResult<mozilla::ipc::IPCResult> {
+  mozilla::ipc::IPCResult mErrorValue;
+
+  template <typename V, typename E2>
+  friend class Result;
+
+ public:
+  explicit GenericErrorResult(mozilla::ipc::IPCResult aErrorValue)
+      : mErrorValue(aErrorValue) {
+    MOZ_ASSERT(!aErrorValue);
+  }
+
+  GenericErrorResult(mozilla::ipc::IPCResult aErrorValue,
+                     const ErrorPropagationTag&)
+      : GenericErrorResult(aErrorValue) {}
+
+  operator mozilla::ipc::IPCResult() const { return mErrorValue; }
+};
+
+namespace dom::quota {
+
+extern const char kQuotaGenericDelimiter;
+
+// Telemetry keys to indicate types of errors.
+#ifdef NIGHTLY_BUILD
+extern const nsLiteralCString kQuotaInternalError;
+extern const nsLiteralCString kQuotaExternalError;
+#else
+// No need for these when we're not collecting telemetry.
+#  define kQuotaInternalError
+#  define kQuotaExternalError
+#endif
+
+class BackgroundThreadObject {
+ protected:
+  nsCOMPtr<nsISerialEventTarget> mOwningThread;
+
+ public:
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+  nsISerialEventTarget* OwningThread() const;
+
+ protected:
+  BackgroundThreadObject();
+
+  explicit BackgroundThreadObject(nsISerialEventTarget* aOwningThread);
+};
+
+MOZ_COLD void ReportInternalError(const char* aFile, uint32_t aLine,
+                                  const char* aStr);
+
+LogModule* GetQuotaManagerLogger();
+
+void AnonymizeCString(nsACString& aCString);
+
+inline auto AnonymizedCString(const nsACString& aCString) {
+  nsAutoCString result{aCString};
+  AnonymizeCString(result);
+  return result;
+}
+
+void AnonymizeOriginString(nsACString& aOriginString);
+
+inline auto AnonymizedOriginString(const nsACString& aOriginString) {
+  nsAutoCString result{aOriginString};
+  AnonymizeOriginString(result);
+  return result;
+}
+
+#ifdef XP_WIN
+void CacheUseDOSDevicePathSyntaxPrefValue();
+#endif
+
+Result<nsCOMPtr<nsIFile>, nsresult> QM_NewLocalFile(const nsAString& aPath);
+
+nsDependentCSubstring GetLeafName(const nsACString& aPath);
+
+Result<nsCOMPtr<nsIFile>, nsresult> CloneFileAndAppend(
+    nsIFile& aDirectory, const nsAString& aPathElement);
+
+enum class nsIFileKind {
+  ExistsAsDirectory,
+  ExistsAsFile,
+  DoesNotExist,
+};
+
+// XXX We can use this outside of QM and its clients as well, probably. Maybe it
+// could be moved to xpcom/io?
+Result<nsIFileKind, nsresult> GetDirEntryKind(nsIFile& aFile);
+
+Result<nsCOMPtr<mozIStorageStatement>, nsresult> CreateStatement(
+    mozIStorageConnection& aConnection, const nsACString& aStatementString);
+
+enum class SingleStepResult { AssertHasResult, ReturnNullIfNoResult };
+
+template <SingleStepResult ResultHandling>
+using SingleStepSuccessType =
+    std::conditional_t<ResultHandling == SingleStepResult::AssertHasResult,
+                       NotNull<nsCOMPtr<mozIStorageStatement>>,
+                       nsCOMPtr<mozIStorageStatement>>;
+
+template <SingleStepResult ResultHandling>
+Result<SingleStepSuccessType<ResultHandling>, nsresult> ExecuteSingleStep(
+    nsCOMPtr<mozIStorageStatement>&& aStatement);
+
+// Creates a statement with the specified aStatementString, executes a single
+// step, and returns the statement.
+// Depending on the value ResultHandling,
+// - it is asserted that there is a result (default resp.
+//   SingleStepResult::AssertHasResult), and the success type is
+//   MovingNotNull<nsCOMPtr<mozIStorageStatement>>
+// - it is asserted that there is no result, and the success type is Ok
+// - in case there is no result, nullptr is returned, and the success type is
+//   nsCOMPtr<mozIStorageStatement>
+// Any other errors are always propagated.
+template <SingleStepResult ResultHandling = SingleStepResult::AssertHasResult>
+Result<SingleStepSuccessType<ResultHandling>, nsresult>
+CreateAndExecuteSingleStepStatement(mozIStorageConnection& aConnection,
+                                    const nsACString& aStatementString);
+
+namespace detail {
+
+// Determine the absolute path of the root of our built source tree so we can
+// derive source-relative paths for non-exported header files in
+// MakeSourceFileRelativePath. Exported header files end up in the objdir and
+// we have GetObjdirDistIncludeTreeBase for that.
+nsDependentCSubstring GetSourceTreeBase();
+
+// Determine the absolute path of the root of our built OBJDIR/dist/include
+// directory. The aQuotaCommonHPath argument cleverly defaults to __FILE__
+// initialized in our exported header; no argument should ever be provided to
+// this method. GetSourceTreeBase handles identifying the root of the source
+// tree.
+nsDependentCSubstring GetObjdirDistIncludeTreeBase(
+    const nsLiteralCString& aQuotaCommonHPath = nsLiteralCString(__FILE__));
+
+nsDependentCSubstring MakeSourceFileRelativePath(
+    const nsACString& aSourceFilePath);
+
+}  // namespace detail
+
+enum class Severity {
+  Error,
+  Warning,
+  Info,
+  Verbose,
+};
+
+#ifdef QM_LOG_ERROR_ENABLED
+#  ifdef QM_ERROR_STACKS_ENABLED
+using ResultType = Variant<QMResult, nsresult, Nothing>;
+
+void LogError(const nsACString& aExpr, const ResultType& aResult,
+              const nsACString& aSourceFilePath, int32_t aSourceFileLine,
+              Severity aSeverity)
+#  else
+void LogError(const nsACString& aExpr, Maybe<nsresult> aMaybeRv,
+              const nsACString& aSourceFilePath, int32_t aSourceFileLine,
+              Severity aSeverity)
+#  endif
+    ;
+#endif
+
+#ifdef DEBUG
+Result<bool, nsresult> WarnIfFileIsUnknown(nsIFile& aFile,
+                                           const char* aSourceFilePath,
+                                           int32_t aSourceFileLine);
+#endif
+
+// As HandleError is a function that will only be called in error cases, it is
+// marked with MOZ_COLD to avoid bloating the code of calling functions, if it's
+// not empty.
+//
+// For the same reason, the string-ish parameters are of type const char* rather
+// than any ns*String type, to minimize the code at each call site. This
+// deliberately de-optimizes runtime performance, which is uncritical during
+// error handling.
+//
+// This functions are not intended to be called
+// directly, they should only be called from the QM_* macros.
+#ifdef QM_LOG_ERROR_ENABLED
+template <typename T>
+MOZ_COLD MOZ_NEVER_INLINE void HandleError(const char* aExpr, const T& aRv,
+                                           const char* aSourceFilePath,
+                                           int32_t aSourceFileLine,
+                                           const Severity aSeverity) {
+#  ifdef QM_ERROR_STACKS_ENABLED
+  if constexpr (std::is_same_v<T, QMResult> || std::is_same_v<T, nsresult>) {
+    mozilla::dom::quota::LogError(nsDependentCString(aExpr), ResultType(aRv),
+                                  nsDependentCString(aSourceFilePath),
+                                  aSourceFileLine, aSeverity);
+  } else {
+    mozilla::dom::quota::LogError(
+        nsDependentCString(aExpr), ResultType(Nothing{}),
+        nsDependentCString(aSourceFilePath), aSourceFileLine, aSeverity);
+  }
+#  else
+  if constexpr (std::is_same_v<T, nsresult>) {
+    mozilla::dom::quota::LogError(nsDependentCString(aExpr), Some(aRv),
+                                  nsDependentCString(aSourceFilePath),
+                                  aSourceFileLine, aSeverity);
+  } else {
+    mozilla::dom::quota::LogError(nsDependentCString(aExpr), Nothing{},
+                                  nsDependentCString(aSourceFilePath),
+                                  aSourceFileLine, aSeverity);
+  }
+#  endif
+}
+#else
+template <typename T>
+MOZ_ALWAYS_INLINE constexpr void HandleError(const char* aExpr, const T& aRv,
+                                             const char* aSourceFilePath,
+                                             int32_t aSourceFileLine,
+                                             const Severity aSeverity) {}
+#endif
+
+template <typename T>
+Nothing HandleErrorReturnNothing(const char* aExpr, const T& aRv,
+                                 const char* aSourceFilePath,
+                                 int32_t aSourceFileLine,
+                                 const Severity aSeverity) {
+  HandleError(aExpr, aRv, aSourceFilePath, aSourceFileLine, aSeverity);
+  return Nothing();
+}
+
+template <typename T, typename CleanupFunc>
+Nothing HandleErrorWithCleanupReturnNothing(const char* aExpr, const T& aRv,
+                                            const char* aSourceFilePath,
+                                            int32_t aSourceFileLine,
+                                            const Severity aSeverity,
+                                            CleanupFunc&& aCleanupFunc) {
+  HandleError(aExpr, aRv, aSourceFilePath, aSourceFileLine, aSeverity);
+  std::forward<CleanupFunc>(aCleanupFunc)(aRv);
+  return Nothing();
+}
+
+template <typename T, typename CustomRetVal>
+auto HandleCustomRetVal(const char* aFunc, const char* aExpr, const T& aRv,
+                        CustomRetVal&& aCustomRetVal) {
+  if constexpr (std::is_invocable<CustomRetVal, const char*,
+                                  const char*>::value) {
+    return aCustomRetVal(aFunc, aExpr);
+  } else if constexpr (std::is_invocable<CustomRetVal, const char*,
+                                         const T&>::value) {
+    return aCustomRetVal(aFunc, aRv);
+  } else if constexpr (std::is_invocable<CustomRetVal, const T&>::value) {
+    return aCustomRetVal(aRv);
+  } else {
+    return std::forward<CustomRetVal>(aCustomRetVal);
+  }
+}
+
+template <SingleStepResult ResultHandling = SingleStepResult::AssertHasResult,
+          typename BindFunctor>
+Result<SingleStepSuccessType<ResultHandling>, nsresult>
+CreateAndExecuteSingleStepStatement(mozIStorageConnection& aConnection,
+                                    const nsACString& aStatementString,
+                                    BindFunctor aBindFunctor) {
+  QM_TRY_UNWRAP(auto stmt, CreateStatement(aConnection, aStatementString));
+
+  QM_TRY(aBindFunctor(*stmt));
+
+  return ExecuteSingleStep<ResultHandling>(std::move(stmt));
+}
+
+template <typename StepFunc>
+Result<Ok, nsresult> CollectWhileHasResult(mozIStorageStatement& aStmt,
+                                           StepFunc&& aStepFunc) {
+  return CollectWhile(
+      [&aStmt] {
+        QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER(aStmt, ExecuteStep));
+      },
+      [&aStmt, &aStepFunc] { return aStepFunc(aStmt); });
+}
+
+template <typename StepFunc,
+          typename ArrayType = nsTArray<typename std::invoke_result_t<
+              StepFunc, mozIStorageStatement&>::ok_type>>
+auto CollectElementsWhileHasResult(mozIStorageStatement& aStmt,
+                                   StepFunc&& aStepFunc)
+    -> Result<ArrayType, nsresult> {
+  ArrayType res;
+
+  QM_TRY(CollectWhileHasResult(
+      aStmt, [&aStepFunc, &res](auto& stmt) -> Result<Ok, nsresult> {
+        QM_TRY_UNWRAP(auto element, aStepFunc(stmt));
+        res.AppendElement(std::move(element));
+        return Ok{};
+      }));
+
+  return std::move(res);
+}
+
+template <typename ArrayType, typename StepFunc>
+auto CollectElementsWhileHasResultTyped(mozIStorageStatement& aStmt,
+                                        StepFunc&& aStepFunc) {
+  return CollectElementsWhileHasResult<StepFunc, ArrayType>(
+      aStmt, std::forward<StepFunc>(aStepFunc));
+}
+
+namespace detail {
+template <typename Cancel, typename Body>
+Result<mozilla::Ok, nsresult> CollectEachFile(nsIFile& aDirectory,
+                                              const Cancel& aCancel,
+                                              const Body& aBody) {
+  QM_TRY_INSPECT(const auto& entries, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                          nsCOMPtr<nsIDirectoryEnumerator>,
+                                          aDirectory, GetDirectoryEntries));
+
+  return CollectEach(
+      [&entries, &aCancel]() -> Result<nsCOMPtr<nsIFile>, nsresult> {
+        if (aCancel()) {
+          return nsCOMPtr<nsIFile>{};
+        }
+
+        QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCOMPtr<nsIFile>,
+                                                        entries, GetNextFile));
+      },
+      aBody);
+}
+}  // namespace detail
+
+template <typename Body>
+Result<mozilla::Ok, nsresult> CollectEachFile(nsIFile& aDirectory,
+                                              const Body& aBody) {
+  return detail::CollectEachFile(
+      aDirectory, [] { return false; }, aBody);
+}
+
+template <typename Body>
+Result<mozilla::Ok, nsresult> CollectEachFileAtomicCancelable(
+    nsIFile& aDirectory, const Atomic<bool>& aCanceled, const Body& aBody) {
+  return detail::CollectEachFile(
+      aDirectory, [&aCanceled] { return static_cast<bool>(aCanceled); }, aBody);
+}
+
+template <typename T, typename Body>
+auto ReduceEachFileAtomicCancelable(nsIFile& aDirectory,
+                                    const Atomic<bool>& aCanceled, T aInit,
+                                    const Body& aBody) -> Result<T, nsresult> {
+  QM_TRY_INSPECT(const auto& entries, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                          nsCOMPtr<nsIDirectoryEnumerator>,
+                                          aDirectory, GetDirectoryEntries));
+
+  return ReduceEach(
+      [&entries, &aCanceled]() -> Result<nsCOMPtr<nsIFile>, nsresult> {
+        if (aCanceled) {
+          return nsCOMPtr<nsIFile>{};
+        }
+
+        QM_TRY_RETURN(MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(nsCOMPtr<nsIFile>,
+                                                        entries, GetNextFile));
+      },
+      std::move(aInit), aBody);
+}
+
+constexpr bool IsDatabaseCorruptionError(const nsresult aRv) {
+  return aRv == NS_ERROR_FILE_CORRUPTED || aRv == NS_ERROR_STORAGE_IOERR;
+}
+
+template <typename Func>
+auto CallWithDelayedRetriesIfAccessDenied(Func&& aFunc, uint32_t aMaxRetries,
+                                          uint32_t aDelayMs)
+    -> Result<typename std::invoke_result_t<Func>::ok_type, nsresult> {
+  uint32_t retries = 0;
+
+  while (true) {
+    auto result = std::forward<Func>(aFunc)();
+
+    if (result.isOk()) {
+      return result;
+    }
+
+    if (result.inspectErr() != NS_ERROR_FILE_IS_LOCKED &&
+        result.inspectErr() != NS_ERROR_FILE_ACCESS_DENIED) {
+      return result;
+    }
+
+    if (retries++ >= aMaxRetries) {
+      return result;
+    }
+
+    PR_Sleep(PR_MillisecondsToInterval(aDelayMs));
+  }
+}
+
+namespace detail {
+
+template <bool flag = false>
+void UnsupportedReturnType() {
+  static_assert(flag, "Unsupported return type!");
+}
+
+}  // namespace detail
+
+template <typename Initialization, typename StringGenerator, typename Func>
+auto ExecuteInitialization(
+    FirstInitializationAttempts<Initialization, StringGenerator>&
+        aFirstInitializationAttempts,
+    const Initialization aInitialization, Func&& aFunc)
+    -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                      Initialization, StringGenerator>&> {
+  return aFirstInitializationAttempts.WithFirstInitializationAttempt(
+      aInitialization, [&aFunc](auto&& firstInitializationAttempt) {
+        auto res = std::forward<Func>(aFunc)(firstInitializationAttempt);
+
+        const auto rv = [&res]() -> nsresult {
+          using RetType =
+              std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                             Initialization, StringGenerator>&>;
+
+          if constexpr (std::is_same_v<RetType, nsresult>) {
+            return res;
+          } else if constexpr (mozilla::detail::IsResult<RetType>::value &&
+                               std::is_same_v<typename RetType::err_type,
+                                              nsresult>) {
+            return res.isOk() ? NS_OK : res.inspectErr();
+          } else {
+            detail::UnsupportedReturnType();
+          }
+        }();
+
+        // NS_ERROR_ABORT signals a non-fatal, recoverable problem during
+        // initialization. We do not want these kind of failures to count
+        // against our overall first initialization attempt telemetry. Thus we
+        // just ignore this kind of failure and keep
+        // aFirstInitializationAttempts unflagged to stay ready to record a real
+        // success or failure on the next attempt.
+        if (rv == NS_ERROR_ABORT) {
+          return res;
+        }
+
+        if (!firstInitializationAttempt.Recorded()) {
+          firstInitializationAttempt.Record(rv);
+        }
+
+        return res;
+      });
+}
+
+template <typename Initialization, typename StringGenerator, typename Func>
+auto ExecuteInitialization(
+    FirstInitializationAttempts<Initialization, StringGenerator>&
+        aFirstInitializationAttempts,
+    const Initialization aInitialization, const nsACString& aContext,
+    Func&& aFunc)
+    -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                      Initialization, StringGenerator>&> {
+  return ExecuteInitialization(
+      aFirstInitializationAttempts, aInitialization,
+      [&](const auto& firstInitializationAttempt) -> decltype(auto) {
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+        const auto maybeScopedLogExtraInfo =
+            firstInitializationAttempt.Recorded()
+                ? Nothing{}
+                : Some(ScopedLogExtraInfo{ScopedLogExtraInfo::kTagContext,
+                                          aContext});
+#endif
+
+        return std::forward<Func>(aFunc)(firstInitializationAttempt);
+      });
+}
+
+}  // namespace dom::quota
+}  // namespace mozilla
+
+#endif  // mozilla_dom_quota_quotacommon_h__
diff --git a/dom/quota/QuotaManager.h b/dom/quota/QuotaManager.h
new file mode 100644
index 0000000000..e18454909f
--- /dev/null
+++ b/dom/quota/QuotaManager.h
@@ -0,0 +1,676 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_quotamanager_h__
+#define mozilla_dom_quota_quotamanager_h__
+
+#include <cstdint>
+#include <utility>
+#include "Client.h"
+#include "ErrorList.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/InitializedOnce.h"
+#include "mozilla/MozPromise.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Result.h"
+#include "mozilla/dom/Nullable.h"
+#include "mozilla/dom/ipc/IdType.h"
+#include "mozilla/dom/quota/Assertions.h"
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "mozilla/dom/quota/ForwardDecls.h"
+#include "mozilla/dom/quota/InitializationTypes.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "nsCOMPtr.h"
+#include "nsClassHashtable.h"
+#include "nsTHashMap.h"
+#include "nsDebug.h"
+#include "nsHashKeys.h"
+#include "nsISupports.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nsTStringRepr.h"
+#include "nscore.h"
+#include "prenv.h"
+
+#define QUOTA_MANAGER_CONTRACTID "@mozilla.org/dom/quota/manager;1"
+
+class mozIStorageConnection;
+class nsIEventTarget;
+class nsIFile;
+class nsIPrincipal;
+class nsIRunnable;
+class nsIThread;
+class nsITimer;
+class nsPIDOMWindowOuter;
+
+namespace mozilla {
+
+class OriginAttributes;
+
+namespace ipc {
+
+class PrincipalInfo;
+
+}  // namespace ipc
+
+}  // namespace mozilla
+
+namespace mozilla::dom::quota {
+
+class CanonicalQuotaObject;
+class ClientUsageArray;
+class ClientDirectoryLock;
+class DirectoryLockImpl;
+class GroupInfo;
+class GroupInfoPair;
+class OriginDirectoryLock;
+class OriginInfo;
+class OriginScope;
+class QuotaObject;
+class UniversalDirectoryLock;
+
+class QuotaManager final : public BackgroundThreadObject {
+  friend class CanonicalQuotaObject;
+  friend class DirectoryLockImpl;
+  friend class GroupInfo;
+  friend class OriginInfo;
+
+  using PrincipalInfo = mozilla::ipc::PrincipalInfo;
+  using DirectoryLockTable =
+      nsClassHashtable<nsCStringHashKey, nsTArray<NotNull<DirectoryLockImpl*>>>;
+
+  class Observer;
+
+ public:
+  QuotaManager(const nsAString& aBasePath, const nsAString& aStorageName);
+
+  NS_INLINE_DECL_REFCOUNTING(QuotaManager)
+
+  static nsresult Initialize();
+
+  static bool IsRunningXPCShellTests() {
+    static bool kRunningXPCShellTests =
+        !!PR_GetEnv("XPCSHELL_TEST_PROFILE_DIR");
+    return kRunningXPCShellTests;
+  }
+
+  static bool IsRunningGTests() {
+    static bool kRunningGTests = !!PR_GetEnv("MOZ_RUN_GTEST");
+    return kRunningGTests;
+  }
+
+  static const char kReplaceChars[];
+  static const char16_t kReplaceChars16[];
+
+  static Result<MovingNotNull<RefPtr<QuotaManager>>, nsresult> GetOrCreate();
+
+  static Result<Ok, nsresult> EnsureCreated();
+
+  // Returns a non-owning reference.
+  static QuotaManager* Get();
+
+  // Use only in gtests!
+  static nsIObserver* GetObserver();
+
+  // Returns true if we've begun the shutdown process.
+  static bool IsShuttingDown();
+
+  static void ShutdownInstance();
+
+  // Use only in gtests!
+  static void Reset();
+
+  static bool IsOSMetadata(const nsAString& aFileName);
+
+  static bool IsDotFile(const nsAString& aFileName);
+
+  bool IsOriginInitialized(const nsACString& aOrigin) const {
+    AssertIsOnIOThread();
+
+    return mInitializedOrigins.Contains(aOrigin);
+  }
+
+  bool IsTemporaryStorageInitialized() const {
+    AssertIsOnIOThread();
+
+    return mTemporaryStorageInitialized;
+  }
+
+  /**
+   * For initialization of an origin where the directory already exists. This is
+   * used by EnsureTemporaryStorageIsInitialized/InitializeRepository once it
+   * has tallied origin usage by calling each of the QuotaClient InitOrigin
+   * methods.
+   */
+  void InitQuotaForOrigin(const FullOriginMetadata& aFullOriginMetadata,
+                          const ClientUsageArray& aClientUsages,
+                          uint64_t aUsageBytes);
+
+  /**
+   * For use in special-cases like LSNG where we need to be able to know that
+   * there is no data stored for an origin. LSNG knows that there is 0 usage for
+   * its storage of an origin and wants to make sure there is a QuotaObject
+   * tracking this. This method will create a non-persisted, 0-usage,
+   * mDirectoryExists=false OriginInfo if there isn't already an OriginInfo. If
+   * an OriginInfo already exists, it will be left as-is, because that implies a
+   * different client has usages for the origin (and there's no need to add
+   * LSNG's 0 usage to the QuotaObject).
+   */
+  void EnsureQuotaForOrigin(const OriginMetadata& aOriginMetadata);
+
+  /**
+   * For use when creating an origin directory. It's possible that origin usage
+   * is already being tracked due to a call to EnsureQuotaForOrigin, and in that
+   * case we need to update the existing OriginInfo rather than create a new
+   * one.
+   *
+   * @return last access time of the origin.
+   */
+  int64_t NoteOriginDirectoryCreated(const OriginMetadata& aOriginMetadata,
+                                     bool aPersisted);
+
+  // XXX clients can use QuotaObject instead of calling this method directly.
+  void DecreaseUsageForClient(const ClientMetadata& aClientMetadata,
+                              int64_t aSize);
+
+  void ResetUsageForClient(const ClientMetadata& aClientMetadata);
+
+  UsageInfo GetUsageForClient(PersistenceType aPersistenceType,
+                              const OriginMetadata& aOriginMetadata,
+                              Client::Type aClientType);
+
+  void UpdateOriginAccessTime(PersistenceType aPersistenceType,
+                              const OriginMetadata& aOriginMetadata);
+
+  void RemoveQuota();
+
+  void RemoveQuotaForOrigin(PersistenceType aPersistenceType,
+                            const OriginMetadata& aOriginMetadata) {
+    MutexAutoLock lock(mQuotaMutex);
+    LockedRemoveQuotaForOrigin(aOriginMetadata);
+  }
+
+  nsresult LoadQuota();
+
+  void UnloadQuota();
+
+  already_AddRefed<QuotaObject> GetQuotaObject(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      Client::Type aClientType, nsIFile* aFile, int64_t aFileSize = -1,
+      int64_t* aFileSizeOut = nullptr);
+
+  already_AddRefed<QuotaObject> GetQuotaObject(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      Client::Type aClientType, const nsAString& aPath, int64_t aFileSize = -1,
+      int64_t* aFileSizeOut = nullptr);
+
+  already_AddRefed<QuotaObject> GetQuotaObject(const int64_t aDirectoryLockId,
+                                               const nsAString& aPath);
+
+  Nullable<bool> OriginPersisted(const OriginMetadata& aOriginMetadata);
+
+  void PersistOrigin(const OriginMetadata& aOriginMetadata);
+
+  using DirectoryLockIdTableArray =
+      AutoTArray<Client::DirectoryLockIdTable, Client::TYPE_MAX>;
+  void AbortOperationsForLocks(const DirectoryLockIdTableArray& aLockIds);
+
+  // Called when a process is being shot down. Aborts any running operations
+  // for the given process.
+  void AbortOperationsForProcess(ContentParentId aContentParentId);
+
+  Result<nsCOMPtr<nsIFile>, nsresult> GetDirectoryForOrigin(
+      PersistenceType aPersistenceType, const nsACString& aASCIIOrigin) const;
+
+  nsresult RestoreDirectoryMetadata2(nsIFile* aDirectory);
+
+  // XXX Remove aPersistenceType argument once the persistence type is stored
+  // in the metadata file.
+  Result<FullOriginMetadata, nsresult> LoadFullOriginMetadata(
+      nsIFile* aDirectory, PersistenceType aPersistenceType);
+
+  Result<FullOriginMetadata, nsresult> LoadFullOriginMetadataWithRestore(
+      nsIFile* aDirectory);
+
+  // This is the main entry point into the QuotaManager API.
+  // Any storage API implementation (quota client) that participates in
+  // centralized quota and storage handling should call this method to get
+  // a directory lock which will protect client's files from being deleted
+  // while they are still in use.
+  // After a lock is acquired, client is notified via the open listener's
+  // method DirectoryLockAcquired. If the lock couldn't be acquired, client
+  // gets DirectoryLockFailed notification.
+  // A lock is a reference counted object and at the time DirectoryLockAcquired
+  // is called, quota manager holds just one strong reference to it which is
+  // then immediatelly cleared by quota manager. So it's up to client to add
+  // a new reference in order to keep the lock alive.
+  // Unlocking is simply done by dropping all references to the lock object.
+  // In other words, protection which the lock represents dies with the lock
+  // object itself.
+  RefPtr<ClientDirectoryLock> CreateDirectoryLock(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata,
+      Client::Type aClientType, bool aExclusive);
+
+  // XXX RemoveMe once bug 1170279 gets fixed.
+  RefPtr<UniversalDirectoryLock> CreateDirectoryLockInternal(
+      const Nullable<PersistenceType>& aPersistenceType,
+      const OriginScope& aOriginScope,
+      const Nullable<Client::Type>& aClientType, bool aExclusive);
+
+  // Collect inactive and the least recently used origins.
+  uint64_t CollectOriginsForEviction(
+      uint64_t aMinSizeToBeFreed,
+      nsTArray<RefPtr<OriginDirectoryLock>>& aLocks);
+
+  /**
+   * Helper method to invoke the provided predicate on all "pending" OriginInfo
+   * instances. These are origins for which the origin directory has not yet
+   * been created but for which quota is already being tracked. This happens,
+   * for example, for the LocalStorage client where an origin that previously
+   * was not using LocalStorage can start issuing writes which it buffers until
+   * eventually flushing them. We defer creating the origin directory for as
+   * long as possible in that case, so the directory won't exist. Logic that
+   * would otherwise only consult the filesystem also needs to use this method.
+   */
+  template <typename P>
+  void CollectPendingOriginsForListing(P aPredicate);
+
+  bool IsStorageInitialized() const {
+    AssertIsOnIOThread();
+    return static_cast<bool>(mStorageConnection);
+  }
+
+  void AssertStorageIsInitialized() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+  nsresult EnsureStorageIsInitialized();
+
+  // Returns a pair of an nsIFile object referring to the directory, and a bool
+  // indicating whether the directory was newly created.
+  Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult>
+  EnsurePersistentOriginIsInitialized(const OriginMetadata& aOriginMetadata);
+
+  // Returns a pair of an nsIFile object referring to the directory, and a bool
+  // indicating whether the directory was newly created.
+  Result<std::pair<nsCOMPtr<nsIFile>, bool>, nsresult>
+  EnsureTemporaryOriginIsInitialized(PersistenceType aPersistenceType,
+                                     const OriginMetadata& aOriginMetadata);
+
+  nsresult EnsureTemporaryStorageIsInitialized();
+
+  RefPtr<BoolPromise> ShutdownStorage();
+
+  void ShutdownStorageInternal();
+
+  // Returns a bool indicating whether the directory was newly created.
+  Result<bool, nsresult> EnsureOriginDirectory(nsIFile& aDirectory);
+
+  nsresult AboutToClearOrigins(
+      const Nullable<PersistenceType>& aPersistenceType,
+      const OriginScope& aOriginScope,
+      const Nullable<Client::Type>& aClientType);
+
+  void OriginClearCompleted(PersistenceType aPersistenceType,
+                            const nsACString& aOrigin,
+                            const Nullable<Client::Type>& aClientType);
+
+  void StartIdleMaintenance() {
+    AssertIsOnOwningThread();
+
+    for (const auto& client : *mClients) {
+      client->StartIdleMaintenance();
+    }
+  }
+
+  void StopIdleMaintenance() {
+    AssertIsOnOwningThread();
+
+    for (const auto& client : *mClients) {
+      client->StopIdleMaintenance();
+    }
+  }
+
+  void AssertCurrentThreadOwnsQuotaMutex() {
+    mQuotaMutex.AssertCurrentThreadOwns();
+  }
+
+  nsIThread* IOThread() { return mIOThread->get(); }
+
+  Client* GetClient(Client::Type aClientType);
+
+  const AutoTArray<Client::Type, Client::TYPE_MAX>& AllClientTypes();
+
+  const nsString& GetBasePath() const { return mBasePath; }
+
+  const nsString& GetStorageName() const { return mStorageName; }
+
+  const nsString& GetStoragePath() const { return *mStoragePath; }
+
+  const nsString& GetStoragePath(PersistenceType aPersistenceType) const {
+    if (aPersistenceType == PERSISTENCE_TYPE_PERSISTENT) {
+      return *mPermanentStoragePath;
+    }
+
+    if (aPersistenceType == PERSISTENCE_TYPE_TEMPORARY) {
+      return *mTemporaryStoragePath;
+    }
+
+    MOZ_ASSERT(aPersistenceType == PERSISTENCE_TYPE_DEFAULT);
+
+    return *mDefaultStoragePath;
+  }
+
+  uint64_t GetGroupLimit() const;
+
+  std::pair<uint64_t, uint64_t> GetUsageAndLimitForEstimate(
+      const OriginMetadata& aOriginMetadata);
+
+  uint64_t GetOriginUsage(const PrincipalMetadata& aPrincipalMetadata);
+
+  Maybe<FullOriginMetadata> GetFullOriginMetadata(
+      const OriginMetadata& aOriginMetadata);
+
+  void NotifyStoragePressure(uint64_t aUsage);
+
+  // Record a quota client shutdown step, if shutting down.
+  // Assumes that the QuotaManager singleton is alive.
+  static void MaybeRecordQuotaClientShutdownStep(
+      const Client::Type aClientType, const nsACString& aStepDescription);
+
+  // Record a quota client shutdown step, if shutting down.
+  // Checks if the QuotaManager singleton is alive.
+  static void SafeMaybeRecordQuotaClientShutdownStep(
+      Client::Type aClientType, const nsACString& aStepDescription);
+
+  // Record a quota manager shutdown step, use only if shutdown is active.
+  void RecordQuotaManagerShutdownStep(const nsACString& aStepDescription);
+
+  // Record a quota manager shutdown step, if shutting down.
+  void MaybeRecordQuotaManagerShutdownStep(const nsACString& aStepDescription);
+
+  template <typename F>
+  void MaybeRecordQuotaManagerShutdownStepWith(F&& aFunc);
+
+  static void GetStorageId(PersistenceType aPersistenceType,
+                           const nsACString& aOrigin, Client::Type aClientType,
+                           nsACString& aDatabaseId);
+
+  static bool IsPrincipalInfoValid(const PrincipalInfo& aPrincipalInfo);
+
+  static PrincipalMetadata GetInfoFromValidatedPrincipalInfo(
+      const PrincipalInfo& aPrincipalInfo);
+
+  static nsAutoCString GetOriginFromValidatedPrincipalInfo(
+      const PrincipalInfo& aPrincipalInfo);
+
+  static Result<PrincipalMetadata, nsresult> GetInfoFromPrincipal(
+      nsIPrincipal* aPrincipal);
+
+  static Result<nsAutoCString, nsresult> GetOriginFromPrincipal(
+      nsIPrincipal* aPrincipal);
+
+  static Result<nsAutoCString, nsresult> GetOriginFromWindow(
+      nsPIDOMWindowOuter* aWindow);
+
+  static nsLiteralCString GetOriginForChrome();
+
+  static PrincipalMetadata GetInfoForChrome();
+
+  static bool IsOriginInternal(const nsACString& aOrigin);
+
+  static bool AreOriginsEqualOnDisk(const nsACString& aOrigin1,
+                                    const nsACString& aOrigin2);
+
+  static Result<PrincipalInfo, nsresult> ParseOrigin(const nsACString& aOrigin);
+
+  static void InvalidateQuotaCache();
+
+ private:
+  virtual ~QuotaManager();
+
+  nsresult Init();
+
+  void Shutdown();
+
+  void RegisterDirectoryLock(DirectoryLockImpl& aLock);
+
+  void UnregisterDirectoryLock(DirectoryLockImpl& aLock);
+
+  void AddPendingDirectoryLock(DirectoryLockImpl& aLock);
+
+  void RemovePendingDirectoryLock(DirectoryLockImpl& aLock);
+
+  uint64_t LockedCollectOriginsForEviction(
+      uint64_t aMinSizeToBeFreed,
+      nsTArray<RefPtr<OriginDirectoryLock>>& aLocks);
+
+  void LockedRemoveQuotaForOrigin(const OriginMetadata& aOriginMetadata);
+
+  already_AddRefed<GroupInfo> LockedGetOrCreateGroupInfo(
+      PersistenceType aPersistenceType, const nsACString& aSuffix,
+      const nsACString& aGroup);
+
+  already_AddRefed<OriginInfo> LockedGetOriginInfo(
+      PersistenceType aPersistenceType, const OriginMetadata& aOriginMetadata);
+
+  nsresult UpgradeFromIndexedDBDirectoryToPersistentStorageDirectory(
+      nsIFile* aIndexedDBDir);
+
+  nsresult UpgradeFromPersistentStorageDirectoryToDefaultStorageDirectory(
+      nsIFile* aPersistentStorageDir);
+
+  nsresult MaybeUpgradeToDefaultStorageDirectory(nsIFile& aStorageFile);
+
+  template <typename Helper>
+  nsresult UpgradeStorage(const int32_t aOldVersion, const int32_t aNewVersion,
+                          mozIStorageConnection* aConnection);
+
+  nsresult UpgradeStorageFrom0_0To1_0(mozIStorageConnection* aConnection);
+
+  nsresult UpgradeStorageFrom1_0To2_0(mozIStorageConnection* aConnection);
+
+  nsresult UpgradeStorageFrom2_0To2_1(mozIStorageConnection* aConnection);
+
+  nsresult UpgradeStorageFrom2_1To2_2(mozIStorageConnection* aConnection);
+
+  nsresult UpgradeStorageFrom2_2To2_3(mozIStorageConnection* aConnection);
+
+  nsresult MaybeCreateOrUpgradeStorage(mozIStorageConnection& aConnection);
+
+  OkOrErr MaybeRemoveLocalStorageArchiveTmpFile();
+
+  nsresult MaybeRemoveLocalStorageDataAndArchive(nsIFile& aLsArchiveFile);
+
+  nsresult MaybeRemoveLocalStorageDirectories();
+
+  Result<Ok, nsresult> CopyLocalStorageArchiveFromWebAppsStore(
+      nsIFile& aLsArchiveFile) const;
+
+  Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+  CreateLocalStorageArchiveConnection(nsIFile& aLsArchiveFile) const;
+
+  Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+  RecopyLocalStorageArchiveFromWebAppsStore(nsIFile& aLsArchiveFile);
+
+  Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+  DowngradeLocalStorageArchive(nsIFile& aLsArchiveFile);
+
+  Result<nsCOMPtr<mozIStorageConnection>, nsresult>
+  UpgradeLocalStorageArchiveFromLessThan4To4(nsIFile& aLsArchiveFile);
+
+  /*
+  nsresult UpgradeLocalStorageArchiveFrom4To5();
+  */
+
+  Result<Ok, nsresult> MaybeCreateOrUpgradeLocalStorageArchive(
+      nsIFile& aLsArchiveFile);
+
+  Result<Ok, nsresult> CreateEmptyLocalStorageArchive(
+      nsIFile& aLsArchiveFile) const;
+
+  template <typename OriginFunc>
+  nsresult InitializeRepository(PersistenceType aPersistenceType,
+                                OriginFunc&& aOriginFunc);
+
+  nsresult InitializeOrigin(PersistenceType aPersistenceType,
+                            const OriginMetadata& aOriginMetadata,
+                            int64_t aAccessTime, bool aPersisted,
+                            nsIFile* aDirectory);
+
+  using OriginInfosFlatTraversable =
+      nsTArray<NotNull<RefPtr<const OriginInfo>>>;
+
+  using OriginInfosNestedTraversable =
+      nsTArray<nsTArray<NotNull<RefPtr<const OriginInfo>>>>;
+
+  OriginInfosNestedTraversable GetOriginInfosExceedingGroupLimit() const;
+
+  OriginInfosNestedTraversable GetOriginInfosExceedingGlobalLimit() const;
+
+  void ClearOrigins(const OriginInfosNestedTraversable& aDoomedOriginInfos);
+
+  void CleanupTemporaryStorage();
+
+  void DeleteFilesForOrigin(PersistenceType aPersistenceType,
+                            const nsACString& aOrigin);
+
+  void FinalizeOriginEviction(nsTArray<RefPtr<OriginDirectoryLock>>&& aLocks);
+
+  Result<Ok, nsresult> ArchiveOrigins(
+      const nsTArray<FullOriginMetadata>& aFullOriginMetadatas);
+
+  void ReleaseIOThreadObjects() {
+    AssertIsOnIOThread();
+
+    for (Client::Type type : AllClientTypes()) {
+      (*mClients)[type]->ReleaseIOThreadObjects();
+    }
+  }
+
+  DirectoryLockTable& GetDirectoryLockTable(PersistenceType aPersistenceType);
+
+  bool IsSanitizedOriginValid(const nsACString& aSanitizedOrigin);
+
+  int64_t GenerateDirectoryLockId();
+
+  bool ShutdownStarted() const;
+
+  void RecordShutdownStep(Maybe<Client::Type> aClientType,
+                          const nsACString& aStepDescription);
+
+  template <typename Func>
+  auto ExecuteInitialization(Initialization aInitialization, Func&& aFunc)
+      -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                        Initialization, StringGenerator>&>;
+
+  template <typename Func>
+  auto ExecuteInitialization(Initialization aInitialization,
+                             const nsACString& aContext, Func&& aFunc)
+      -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                        Initialization, StringGenerator>&>;
+
+  template <typename Func>
+  auto ExecuteOriginInitialization(const nsACString& aOrigin,
+                                   const OriginInitialization aInitialization,
+                                   const nsACString& aContext, Func&& aFunc)
+      -> std::invoke_result_t<Func, const FirstInitializationAttempt<
+                                        Initialization, StringGenerator>&>;
+
+  template <typename Iterator>
+  static void MaybeInsertNonPersistedOriginInfos(
+      Iterator aDest, const RefPtr<GroupInfo>& aTemporaryGroupInfo,
+      const RefPtr<GroupInfo>& aDefaultGroupInfo);
+
+  template <typename Collect, typename Pred>
+  static OriginInfosFlatTraversable CollectLRUOriginInfosUntil(
+      Collect&& aCollect, Pred&& aPred);
+
+  // Thread on which IO is performed.
+  LazyInitializedOnceNotNull<const nsCOMPtr<nsIThread>> mIOThread;
+
+  nsCOMPtr<mozIStorageConnection> mStorageConnection;
+
+  EnumeratedArray<Client::Type, Client::TYPE_MAX, nsCString> mShutdownSteps;
+  LazyInitializedOnce<const TimeStamp> mShutdownStartedAt;
+  Atomic<bool> mShutdownStarted;
+
+  // Accesses to mQuotaManagerShutdownSteps must be protected by mQuotaMutex.
+  nsCString mQuotaManagerShutdownSteps;
+
+  mutable mozilla::Mutex mQuotaMutex MOZ_UNANNOTATED;
+
+  nsClassHashtable<nsCStringHashKey, GroupInfoPair> mGroupInfoPairs;
+
+  // Maintains a list of directory locks that are queued.
+  nsTArray<RefPtr<DirectoryLockImpl>> mPendingDirectoryLocks;
+
+  // Maintains a list of directory locks that are acquired or queued. It can be
+  // accessed on the owning (PBackground) thread only.
+  nsTArray<NotNull<DirectoryLockImpl*>> mDirectoryLocks;
+
+  // Only modifed on the owning thread, but read on multiple threads. Therefore
+  // all modifications (including those on the owning thread) and all reads off
+  // the owning thread must be protected by mQuotaMutex. In other words, only
+  // reads on the owning thread don't have to be protected by mQuotaMutex.
+  nsTHashMap<nsUint64HashKey, NotNull<DirectoryLockImpl*>>
+      mDirectoryLockIdTable;
+
+  // Directory lock tables that are used to update origin access time.
+  DirectoryLockTable mTemporaryDirectoryLockTable;
+  DirectoryLockTable mDefaultDirectoryLockTable;
+
+  // A list of all successfully initialized persistent origins. This list isn't
+  // protected by any mutex but it is only ever touched on the IO thread.
+  nsTArray<nsCString> mInitializedOrigins;
+
+  // A hash table that is used to cache origin parser results for given
+  // sanitized origin strings. This hash table isn't protected by any mutex but
+  // it is only ever touched on the IO thread.
+  nsTHashMap<nsCStringHashKey, bool> mValidOrigins;
+
+  // This array is populated at initialization time and then never modified, so
+  // it can be iterated on any thread.
+  LazyInitializedOnce<const AutoTArray<RefPtr<Client>, Client::TYPE_MAX>>
+      mClients;
+
+  using ClientTypesArray = AutoTArray<Client::Type, Client::TYPE_MAX>;
+  LazyInitializedOnce<const ClientTypesArray> mAllClientTypes;
+  LazyInitializedOnce<const ClientTypesArray> mAllClientTypesExceptLS;
+
+  // This object isn't protected by any mutex but it is only ever touched on
+  // the IO thread.
+  InitializationInfo mInitializationInfo;
+
+  const nsString mBasePath;
+  const nsString mStorageName;
+  LazyInitializedOnce<const nsString> mIndexedDBPath;
+  LazyInitializedOnce<const nsString> mStoragePath;
+  LazyInitializedOnce<const nsString> mStorageArchivesPath;
+  LazyInitializedOnce<const nsString> mPermanentStoragePath;
+  LazyInitializedOnce<const nsString> mTemporaryStoragePath;
+  LazyInitializedOnce<const nsString> mDefaultStoragePath;
+
+  MozPromiseHolder<BoolPromise> mShutdownStoragePromiseHolder;
+
+  uint64_t mTemporaryStorageLimit;
+  uint64_t mTemporaryStorageUsage;
+  int64_t mNextDirectoryLockId;
+  bool mTemporaryStorageInitialized;
+  bool mCacheUsable;
+  bool mShuttingDownStorage;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif /* mozilla_dom_quota_quotamanager_h__ */
diff --git a/dom/quota/QuotaManagerImpl.h b/dom/quota/QuotaManagerImpl.h
new file mode 100644
index 0000000000..1cdd5ed99e
--- /dev/null
+++ b/dom/quota/QuotaManagerImpl.h
@@ -0,0 +1,25 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_QUOTAMANAGERIMPL_H_
+#define DOM_QUOTA_QUOTAMANAGERIMPL_H_
+
+#include "QuotaManager.h"
+
+namespace mozilla::dom::quota {
+
+template <typename F>
+void QuotaManager::MaybeRecordQuotaManagerShutdownStepWith(F&& aFunc) {
+  // Callable on any thread.
+
+  if (IsShuttingDown()) {
+    RecordShutdownStep(Nothing{}, std::forward<F>(aFunc)());
+  }
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_QUOTAMANAGERIMPL_H_
diff --git a/dom/quota/QuotaManagerService.cpp b/dom/quota/QuotaManagerService.cpp
new file mode 100644
index 0000000000..48dcbfa659
--- /dev/null
+++ b/dom/quota/QuotaManagerService.cpp
@@ -0,0 +1,1046 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QuotaManagerService.h"
+
+// Local includes
+#include "ActorsChild.h"
+#include "Client.h"
+#include "QuotaManager.h"
+#include "QuotaRequests.h"
+
+// Global includes
+#include <cstdint>
+#include <cstring>
+#include <utility>
+#include "MainThreadUtils.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/Hal.h"
+#include "mozilla/MacroForEach.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/OriginAttributes.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Services.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/Unused.h"
+#include "mozilla/Variant.h"
+#include "mozilla/dom/quota/PQuota.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "mozilla/fallible.h"
+#include "mozilla/hal_sandbox/PHal.h"
+#include "mozilla/ipc/BackgroundChild.h"
+#include "mozilla/ipc/BackgroundUtils.h"
+#include "mozilla/ipc/PBackgroundChild.h"
+#include "mozilla/ipc/PBackgroundSharedTypes.h"
+#include "nsCOMPtr.h"
+#include "nsContentUtils.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsIObserverService.h"
+#include "nsIPrincipal.h"
+#include "nsIUserIdleService.h"
+#include "nsServiceManagerUtils.h"
+#include "nsStringFwd.h"
+#include "nsXULAppAPI.h"
+#include "nscore.h"
+
+#define PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID "profile-before-change-qm"
+
+namespace mozilla::dom::quota {
+
+using namespace mozilla::ipc;
+
+namespace {
+
+const char kIdleServiceContractId[] = "@mozilla.org/widget/useridleservice;1";
+
+// The number of seconds we will wait after receiving the idle-daily
+// notification before beginning maintenance.
+const uint32_t kIdleObserverTimeSec = 1;
+
+mozilla::StaticRefPtr<QuotaManagerService> gQuotaManagerService;
+
+mozilla::Atomic<bool> gInitialized(false);
+mozilla::Atomic<bool> gClosed(false);
+
+nsresult CheckedPrincipalToPrincipalInfo(nsIPrincipal* aPrincipal,
+                                         PrincipalInfo& aPrincipalInfo) {
+  MOZ_ASSERT(aPrincipal);
+
+  nsresult rv = PrincipalToPrincipalInfo(aPrincipal, &aPrincipalInfo);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (NS_WARN_IF(!QuotaManager::IsPrincipalInfoValid(aPrincipalInfo))) {
+    return NS_ERROR_FAILURE;
+  }
+
+  if (aPrincipalInfo.type() != PrincipalInfo::TContentPrincipalInfo &&
+      aPrincipalInfo.type() != PrincipalInfo::TSystemPrincipalInfo) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  return NS_OK;
+}
+
+nsresult GetClearResetOriginParams(nsIPrincipal* aPrincipal,
+                                   const nsACString& aPersistenceType,
+                                   const nsAString& aClientType,
+                                   ClearResetOriginParams& aParams) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, aParams.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (aPersistenceType.IsVoid()) {
+    aParams.persistenceTypeIsExplicit() = false;
+  } else {
+    const auto maybePersistenceType =
+        PersistenceTypeFromString(aPersistenceType, fallible);
+    if (NS_WARN_IF(maybePersistenceType.isNothing())) {
+      return NS_ERROR_INVALID_ARG;
+    }
+
+    aParams.persistenceType() = maybePersistenceType.value();
+    aParams.persistenceTypeIsExplicit() = true;
+  }
+
+  if (aClientType.IsVoid()) {
+    aParams.clientTypeIsExplicit() = false;
+  } else {
+    Client::Type clientType;
+    bool ok = Client::TypeFromText(aClientType, clientType, fallible);
+    if (NS_WARN_IF(!ok)) {
+      return NS_ERROR_INVALID_ARG;
+    }
+
+    aParams.clientType() = clientType;
+    aParams.clientTypeIsExplicit() = true;
+  }
+
+  return NS_OK;
+}
+
+}  // namespace
+
+class QuotaManagerService::PendingRequestInfo {
+ protected:
+  RefPtr<RequestBase> mRequest;
+
+ public:
+  explicit PendingRequestInfo(RequestBase* aRequest) : mRequest(aRequest) {}
+
+  virtual ~PendingRequestInfo() = default;
+
+  RequestBase* GetRequest() const { return mRequest; }
+
+  virtual nsresult InitiateRequest(QuotaChild* aActor) = 0;
+};
+
+class QuotaManagerService::UsageRequestInfo : public PendingRequestInfo {
+  UsageRequestParams mParams;
+
+ public:
+  UsageRequestInfo(UsageRequest* aRequest, const UsageRequestParams& aParams)
+      : PendingRequestInfo(aRequest), mParams(aParams) {
+    MOZ_ASSERT(aRequest);
+    MOZ_ASSERT(aParams.type() != UsageRequestParams::T__None);
+  }
+
+  virtual nsresult InitiateRequest(QuotaChild* aActor) override;
+};
+
+class QuotaManagerService::RequestInfo : public PendingRequestInfo {
+  RequestParams mParams;
+
+ public:
+  RequestInfo(Request* aRequest, const RequestParams& aParams)
+      : PendingRequestInfo(aRequest), mParams(aParams) {
+    MOZ_ASSERT(aRequest);
+    MOZ_ASSERT(aParams.type() != RequestParams::T__None);
+  }
+
+  virtual nsresult InitiateRequest(QuotaChild* aActor) override;
+};
+
+class QuotaManagerService::IdleMaintenanceInfo : public PendingRequestInfo {
+  const bool mStart;
+
+ public:
+  explicit IdleMaintenanceInfo(bool aStart)
+      : PendingRequestInfo(nullptr), mStart(aStart) {}
+
+  virtual nsresult InitiateRequest(QuotaChild* aActor) override;
+};
+
+QuotaManagerService::QuotaManagerService()
+    : mBackgroundActor(nullptr),
+      mBackgroundActorFailed(false),
+      mIdleObserverRegistered(false) {
+  MOZ_ASSERT(NS_IsMainThread());
+}
+
+QuotaManagerService::~QuotaManagerService() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!mIdleObserverRegistered);
+}
+
+// static
+QuotaManagerService* QuotaManagerService::GetOrCreate() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (gClosed) {
+    MOZ_ASSERT(false, "Calling GetOrCreate() after shutdown!");
+    return nullptr;
+  }
+
+  if (!gQuotaManagerService) {
+    RefPtr<QuotaManagerService> instance(new QuotaManagerService());
+
+    nsresult rv = instance->Init();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return nullptr;
+    }
+
+    if (gInitialized.exchange(true)) {
+      MOZ_ASSERT(false, "Initialized more than once?!");
+    }
+
+    gQuotaManagerService = instance;
+
+    ClearOnShutdown(&gQuotaManagerService);
+  }
+
+  return gQuotaManagerService;
+}
+
+// static
+QuotaManagerService* QuotaManagerService::Get() {
+  // Does not return an owning reference.
+  return gQuotaManagerService;
+}
+
+// static
+already_AddRefed<QuotaManagerService> QuotaManagerService::FactoryCreate() {
+  RefPtr<QuotaManagerService> quotaManagerService = GetOrCreate();
+  return quotaManagerService.forget();
+}
+
+void QuotaManagerService::ClearBackgroundActor() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  mBackgroundActor = nullptr;
+}
+
+void QuotaManagerService::AbortOperationsForProcess(
+    ContentParentId aContentParentId) {
+  MOZ_ASSERT(XRE_IsParentProcess());
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv = EnsureBackgroundActor();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+
+  if (NS_WARN_IF(
+          !mBackgroundActor->SendAbortOperationsForProcess(aContentParentId))) {
+    return;
+  }
+}
+
+nsresult QuotaManagerService::Init() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (XRE_IsParentProcess()) {
+    nsCOMPtr<nsIObserverService> observerService =
+        mozilla::services::GetObserverService();
+    if (NS_WARN_IF(!observerService)) {
+      return NS_ERROR_FAILURE;
+    }
+
+    nsresult rv = observerService->AddObserver(
+        this, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID, false);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+  }
+
+  return NS_OK;
+}
+
+void QuotaManagerService::Destroy() {
+  // Setting the closed flag prevents the service from being recreated.
+  // Don't set it though if there's no real instance created.
+  if (gInitialized && gClosed.exchange(true)) {
+    MOZ_ASSERT(false, "Shutdown more than once?!");
+  }
+
+  delete this;
+}
+
+nsresult QuotaManagerService::EnsureBackgroundActor() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Nothing can be done here if we have previously failed to create a
+  // background actor.
+  if (mBackgroundActorFailed) {
+    return NS_ERROR_FAILURE;
+  }
+
+  if (!mBackgroundActor) {
+    PBackgroundChild* backgroundActor =
+        BackgroundChild::GetOrCreateForCurrentThread();
+    if (NS_WARN_IF(!backgroundActor)) {
+      mBackgroundActorFailed = true;
+      return NS_ERROR_FAILURE;
+    }
+
+    {
+      QuotaChild* actor = new QuotaChild(this);
+
+      mBackgroundActor = static_cast<QuotaChild*>(
+          backgroundActor->SendPQuotaConstructor(actor));
+    }
+  }
+
+  if (!mBackgroundActor) {
+    mBackgroundActorFailed = true;
+    return NS_ERROR_FAILURE;
+  }
+
+  return NS_OK;
+}
+
+nsresult QuotaManagerService::InitiateRequest(PendingRequestInfo& aInfo) {
+  nsresult rv = EnsureBackgroundActor();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = aInfo.InitiateRequest(mBackgroundActor);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+void QuotaManagerService::PerformIdleMaintenance() {
+  using namespace mozilla::hal;
+
+  MOZ_ASSERT(XRE_IsParentProcess());
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // If we're running on battery power then skip all idle maintenance since we
+  // would otherwise be doing lots of disk I/O.
+  BatteryInformation batteryInfo;
+
+#ifdef MOZ_WIDGET_ANDROID
+  // Android XPCShell doesn't load the AndroidBridge that is needed to make
+  // GetCurrentBatteryInformation work...
+  if (!QuotaManager::IsRunningXPCShellTests())
+#endif
+  {
+    // In order to give the correct battery level, hal must have registered
+    // battery observers.
+    RegisterBatteryObserver(this);
+    GetCurrentBatteryInformation(&batteryInfo);
+    UnregisterBatteryObserver(this);
+  }
+
+  // If we're running XPCShell because we always want to be able to test this
+  // code so pretend that we're always charging.
+  if (QuotaManager::IsRunningXPCShellTests()) {
+    batteryInfo.level() = 100;
+    batteryInfo.charging() = true;
+  }
+
+  if (NS_WARN_IF(!batteryInfo.charging())) {
+    return;
+  }
+
+  if (QuotaManager::IsRunningXPCShellTests()) {
+    // We don't want user activity to impact this code if we're running tests.
+    Unused << Observe(nullptr, OBSERVER_TOPIC_IDLE, nullptr);
+  } else if (!mIdleObserverRegistered) {
+    nsCOMPtr<nsIUserIdleService> idleService =
+        do_GetService(kIdleServiceContractId);
+    MOZ_ASSERT(idleService);
+
+    MOZ_ALWAYS_SUCCEEDS(
+        idleService->AddIdleObserver(this, kIdleObserverTimeSec));
+
+    mIdleObserverRegistered = true;
+  }
+}
+
+void QuotaManagerService::RemoveIdleObserver() {
+  MOZ_ASSERT(XRE_IsParentProcess());
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (mIdleObserverRegistered) {
+    nsCOMPtr<nsIUserIdleService> idleService =
+        do_GetService(kIdleServiceContractId);
+    MOZ_ASSERT(idleService);
+
+    // Ignore the return value of RemoveIdleObserver, it may fail if the
+    // observer has already been unregistered during shutdown.
+    Unused << idleService->RemoveIdleObserver(this, kIdleObserverTimeSec);
+
+    mIdleObserverRegistered = false;
+  }
+}
+
+NS_IMPL_ADDREF(QuotaManagerService)
+NS_IMPL_RELEASE_WITH_DESTROY(QuotaManagerService, Destroy())
+NS_IMPL_QUERY_INTERFACE(QuotaManagerService, nsIQuotaManagerService,
+                        nsIObserver)
+
+NS_IMETHODIMP
+QuotaManagerService::StorageName(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  StorageNameParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::StorageInitialized(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  StorageInitializedParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::TemporaryStorageInitialized(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  TemporaryStorageInitializedParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Init(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  InitParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::InitTemporaryStorage(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  InitTemporaryStorageParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::InitializePersistentOrigin(nsIPrincipal* aPrincipal,
+                                                nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  InitializePersistentOriginParams params;
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::InitializeTemporaryOrigin(
+    const nsACString& aPersistenceType, nsIPrincipal* aPrincipal,
+    nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  InitializeTemporaryOriginParams params;
+
+  const auto maybePersistenceType =
+      PersistenceTypeFromString(aPersistenceType, fallible);
+  if (NS_WARN_IF(maybePersistenceType.isNothing())) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  if (NS_WARN_IF(!IsBestEffortPersistenceType(maybePersistenceType.value()))) {
+    return NS_ERROR_FAILURE;
+  }
+
+  params.persistenceType() = maybePersistenceType.value();
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::GetFullOriginMetadata(const nsACString& aPersistenceType,
+                                           nsIPrincipal* aPrincipal,
+                                           nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(nsContentUtils::IsCallerChrome());
+
+  QM_TRY(OkIf(StaticPrefs::dom_quotaManager_testing()), NS_ERROR_UNEXPECTED);
+
+  const auto maybePersistenceType =
+      PersistenceTypeFromString(aPersistenceType, fallible);
+  QM_TRY(OkIf(maybePersistenceType.isSome()), NS_ERROR_INVALID_ARG);
+  QM_TRY(OkIf(IsBestEffortPersistenceType(*maybePersistenceType)),
+         NS_ERROR_INVALID_ARG);
+
+  PrincipalInfo principalInfo;
+  QM_TRY(MOZ_TO_RESULT(PrincipalToPrincipalInfo(aPrincipal, &principalInfo)));
+  QM_TRY(OkIf(QuotaManager::IsPrincipalInfoValid(principalInfo)),
+         NS_ERROR_INVALID_ARG);
+
+  RefPtr<Request> request = new Request();
+
+  GetFullOriginMetadataParams params;
+
+  params.persistenceType() = *maybePersistenceType;
+  params.principalInfo() = std::move(principalInfo);
+
+  RequestInfo info(request, params);
+
+  QM_TRY(MOZ_TO_RESULT(InitiateRequest(info)));
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::GetUsage(nsIQuotaUsageCallback* aCallback, bool aGetAll,
+                              nsIQuotaUsageRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aCallback);
+
+  RefPtr<UsageRequest> request = new UsageRequest(aCallback);
+
+  AllUsageParams params;
+
+  params.getAll() = aGetAll;
+
+  UsageRequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::GetUsageForPrincipal(nsIPrincipal* aPrincipal,
+                                          nsIQuotaUsageCallback* aCallback,
+                                          bool aFromMemory,
+                                          nsIQuotaUsageRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(aCallback);
+
+  RefPtr<UsageRequest> request = new UsageRequest(aPrincipal, aCallback);
+
+  OriginUsageParams params;
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  params.fromMemory() = aFromMemory;
+
+  UsageRequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Clear(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  ClearAllParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::ClearStoragesForOriginAttributesPattern(
+    const nsAString& aPattern, nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  OriginAttributesPattern pattern;
+  MOZ_ALWAYS_TRUE(pattern.Init(aPattern));
+
+  RefPtr<Request> request = new Request();
+
+  ClearDataParams params;
+
+  params.pattern() = pattern;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::ClearStoragesForPrincipal(
+    nsIPrincipal* aPrincipal, const nsACString& aPersistenceType,
+    const nsAString& aClientType, bool aClearAll, nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  nsCString suffix;
+  aPrincipal->OriginAttributesRef().CreateSuffix(suffix);
+
+  if (NS_WARN_IF(aClearAll && !suffix.IsEmpty())) {
+    // The originAttributes should be default originAttributes when the
+    // aClearAll flag is set.
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  RefPtr<Request> request = new Request(aPrincipal);
+
+  ClearResetOriginParams commonParams;
+
+  nsresult rv = GetClearResetOriginParams(aPrincipal, aPersistenceType,
+                                          aClientType, commonParams);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  ClearOriginParams params;
+  params.commonParams() = std::move(commonParams);
+  params.matchAll() = aClearAll;
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Reset(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request();
+
+  ResetAllParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::ResetStoragesForPrincipal(
+    nsIPrincipal* aPrincipal, const nsACString& aPersistenceType,
+    const nsAString& aClientType, nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  if (NS_WARN_IF(!StaticPrefs::dom_quotaManager_testing())) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  RefPtr<Request> request = new Request(aPrincipal);
+
+  ClearResetOriginParams commonParams;
+
+  nsresult rv = GetClearResetOriginParams(aPrincipal, aPersistenceType,
+                                          aClientType, commonParams);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestParams params;
+  params = ResetOriginParams(commonParams);
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Persisted(nsIPrincipal* aPrincipal,
+                               nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(_retval);
+
+  RefPtr<Request> request = new Request(aPrincipal);
+
+  PersistedParams params;
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Persist(nsIPrincipal* aPrincipal,
+                             nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(_retval);
+
+  RefPtr<Request> request = new Request(aPrincipal);
+
+  PersistParams params;
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Estimate(nsIPrincipal* aPrincipal,
+                              nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aPrincipal);
+
+  RefPtr<Request> request = new Request(aPrincipal);
+
+  EstimateParams params;
+
+  nsresult rv =
+      CheckedPrincipalToPrincipalInfo(aPrincipal, params.principalInfo());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RequestInfo info(request, params);
+
+  rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::ListOrigins(nsIQuotaRequest** _retval) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  RefPtr<Request> request = new Request();
+
+  ListOriginsParams params;
+
+  RequestInfo info(request, params);
+
+  nsresult rv = InitiateRequest(info);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  request.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+QuotaManagerService::Observe(nsISupports* aSubject, const char* aTopic,
+                             const char16_t* aData) {
+  MOZ_ASSERT(XRE_IsParentProcess());
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!strcmp(aTopic, PROFILE_BEFORE_CHANGE_QM_OBSERVER_ID)) {
+    RemoveIdleObserver();
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, OBSERVER_TOPIC_IDLE_DAILY)) {
+    PerformIdleMaintenance();
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, OBSERVER_TOPIC_IDLE)) {
+    IdleMaintenanceInfo info(/* aStart */ true);
+
+    nsresult rv = InitiateRequest(info);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, OBSERVER_TOPIC_ACTIVE)) {
+    RemoveIdleObserver();
+
+    IdleMaintenanceInfo info(/* aStart */ false);
+
+    nsresult rv = InitiateRequest(info);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    return NS_OK;
+  }
+
+  MOZ_ASSERT_UNREACHABLE("Should never get here!");
+  return NS_OK;
+}
+
+void QuotaManagerService::Notify(const hal::BatteryInformation& aBatteryInfo) {
+  // This notification is received when battery data changes. We don't need to
+  // deal with this notification.
+}
+
+nsresult QuotaManagerService::UsageRequestInfo::InitiateRequest(
+    QuotaChild* aActor) {
+  MOZ_ASSERT(aActor);
+
+  auto request = static_cast<UsageRequest*>(mRequest.get());
+
+  auto actor = new QuotaUsageRequestChild(request);
+
+  if (!aActor->SendPQuotaUsageRequestConstructor(actor, mParams)) {
+    request->SetError(NS_ERROR_FAILURE);
+    return NS_ERROR_FAILURE;
+  }
+
+  request->SetBackgroundActor(actor);
+
+  return NS_OK;
+}
+
+nsresult QuotaManagerService::RequestInfo::InitiateRequest(QuotaChild* aActor) {
+  MOZ_ASSERT(aActor);
+
+  auto request = static_cast<Request*>(mRequest.get());
+
+  auto actor = new QuotaRequestChild(request);
+
+  if (!aActor->SendPQuotaRequestConstructor(actor, mParams)) {
+    request->SetError(NS_ERROR_FAILURE);
+    return NS_ERROR_FAILURE;
+  }
+
+  return NS_OK;
+}
+
+nsresult QuotaManagerService::IdleMaintenanceInfo::InitiateRequest(
+    QuotaChild* aActor) {
+  MOZ_ASSERT(aActor);
+
+  bool result;
+
+  if (mStart) {
+    result = aActor->SendStartIdleMaintenance();
+  } else {
+    result = aActor->SendStopIdleMaintenance();
+  }
+
+  if (!result) {
+    return NS_ERROR_FAILURE;
+  }
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/QuotaManagerService.h b/dom/quota/QuotaManagerService.h
new file mode 100644
index 0000000000..f8f8c01c31
--- /dev/null
+++ b/dom/quota/QuotaManagerService.h
@@ -0,0 +1,102 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_QuotaManagerService_h
+#define mozilla_dom_quota_QuotaManagerService_h
+
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/HalBatteryInformation.h"
+#include "mozilla/dom/ipc/IdType.h"
+#include "nsIObserver.h"
+#include "nsIQuotaManagerService.h"
+#include "nsISupports.h"
+
+#define QUOTAMANAGER_SERVICE_CONTRACTID \
+  "@mozilla.org/dom/quota-manager-service;1"
+
+class nsIPrincipal;
+class nsIQuotaRequest;
+class nsIQuotaUsageCallback;
+class nsIQuotaUsageRequest;
+
+namespace mozilla {
+namespace ipc {
+
+class PBackgroundChild;
+
+}  // namespace ipc
+
+namespace hal {
+class BatteryInformation;
+}
+
+namespace dom::quota {
+
+class QuotaChild;
+class QuotaManager;
+
+class QuotaManagerService final : public nsIQuotaManagerService,
+                                  public nsIObserver,
+                                  public hal::BatteryObserver {
+  using PBackgroundChild = mozilla::ipc::PBackgroundChild;
+
+  class BackgroundCreateCallback;
+  class PendingRequestInfo;
+  class UsageRequestInfo;
+  class RequestInfo;
+  class IdleMaintenanceInfo;
+
+  QuotaChild* mBackgroundActor;
+
+  bool mBackgroundActorFailed;
+  bool mIdleObserverRegistered;
+
+ public:
+  // Returns a non-owning reference.
+  static QuotaManagerService* GetOrCreate();
+
+  // Returns a non-owning reference.
+  static QuotaManagerService* Get();
+
+  // No one should call this but the factory.
+  static already_AddRefed<QuotaManagerService> FactoryCreate();
+
+  void ClearBackgroundActor();
+
+  // Called when a process is being shot down. Aborts any running operations
+  // for the given process.
+  void AbortOperationsForProcess(ContentParentId aContentParentId);
+
+ private:
+  QuotaManagerService();
+  ~QuotaManagerService();
+
+  nsresult Init();
+
+  void Destroy();
+
+  nsresult EnsureBackgroundActor();
+
+  nsresult InitiateRequest(PendingRequestInfo& aInfo);
+
+  void PerformIdleMaintenance();
+
+  void RemoveIdleObserver();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIQUOTAMANAGERSERVICE
+  NS_DECL_NSIOBSERVER
+
+  // BatteryObserver override
+  void Notify(const hal::BatteryInformation& aBatteryInfo) override;
+};
+
+}  // namespace dom::quota
+}  // namespace mozilla
+
+#endif /* mozilla_dom_quota_QuotaManagerService_h */
diff --git a/dom/quota/QuotaObject.cpp b/dom/quota/QuotaObject.cpp
new file mode 100644
index 0000000000..94256ed1eb
--- /dev/null
+++ b/dom/quota/QuotaObject.cpp
@@ -0,0 +1,73 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QuotaObject.h"
+
+#include "CanonicalQuotaObject.h"
+#include "mozilla/dom/quota/IPCQuotaObject.h"
+#include "mozilla/dom/quota/PRemoteQuotaObject.h"
+#include "mozilla/dom/quota/RemoteQuotaObjectChild.h"
+#include "mozilla/dom/quota/RemoteQuotaObjectParent.h"
+#include "mozilla/dom/quota/RemoteQuotaObjectParentTracker.h"
+#include "mozilla/ipc/BackgroundParent.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "RemoteQuotaObject.h"
+
+namespace mozilla::dom::quota {
+
+CanonicalQuotaObject* QuotaObject::AsCanonicalQuotaObject() {
+  return mIsRemote ? nullptr : static_cast<CanonicalQuotaObject*>(this);
+}
+
+RemoteQuotaObject* QuotaObject::AsRemoteQuotaObject() {
+  return mIsRemote ? static_cast<RemoteQuotaObject*>(this) : nullptr;
+}
+
+IPCQuotaObject QuotaObject::Serialize(nsIInterfaceRequestor* aCallbacks) {
+  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
+  MOZ_RELEASE_ASSERT(!NS_IsMainThread());
+  MOZ_RELEASE_ASSERT(!mozilla::ipc::IsOnBackgroundThread());
+  MOZ_RELEASE_ASSERT(!GetCurrentThreadWorkerPrivate());
+  MOZ_RELEASE_ASSERT(!mIsRemote);
+
+  mozilla::ipc::Endpoint<PRemoteQuotaObjectParent> parentEndpoint;
+  mozilla::ipc::Endpoint<PRemoteQuotaObjectChild> childEndpoint;
+  MOZ_ALWAYS_SUCCEEDS(
+      PRemoteQuotaObject::CreateEndpoints(&parentEndpoint, &childEndpoint));
+
+  nsCOMPtr<RemoteQuotaObjectParentTracker> tracker =
+      do_GetInterface(aCallbacks);
+
+  auto actor =
+      MakeRefPtr<RemoteQuotaObjectParent>(AsCanonicalQuotaObject(), tracker);
+
+  if (tracker) {
+    tracker->RegisterRemoteQuotaObjectParent(WrapNotNull(actor));
+  }
+
+  parentEndpoint.Bind(actor);
+
+  IPCQuotaObject ipcQuotaObject;
+  ipcQuotaObject.childEndpoint() = std::move(childEndpoint);
+
+  return ipcQuotaObject;
+}
+
+// static
+RefPtr<QuotaObject> QuotaObject::Deserialize(IPCQuotaObject& aQuotaObject) {
+  MOZ_RELEASE_ASSERT(!NS_IsMainThread());
+  MOZ_RELEASE_ASSERT(!mozilla::ipc::IsOnBackgroundThread());
+  MOZ_RELEASE_ASSERT(!GetCurrentThreadWorkerPrivate());
+
+  auto actor = MakeRefPtr<RemoteQuotaObjectChild>();
+
+  aQuotaObject.childEndpoint().Bind(actor);
+
+  return MakeRefPtr<RemoteQuotaObject>(actor);
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/QuotaObject.h b/dom/quota/QuotaObject.h
new file mode 100644
index 0000000000..96397faf66
--- /dev/null
+++ b/dom/quota/QuotaObject.h
@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_QUOTAOBJECT_H_
+#define DOM_QUOTA_QUOTAOBJECT_H_
+
+#include "nsISupportsImpl.h"
+
+class nsIInterfaceRequestor;
+
+namespace mozilla::dom::quota {
+
+class CanonicalQuotaObject;
+class IPCQuotaObject;
+class RemoteQuotaObject;
+
+// QuotaObject type is serializable, but only in a restricted manner. The type
+// is only safe to serialize in the parent process and only when the type
+// hasn't been previously deserialized. So the type can be serialized in the
+// parent process and deserialized in a child process or it can be serialized
+// in the parent process and deserialized in the parent process as well
+// (non-e10s mode). The same type can never be serialized/deserialized more
+// than once.
+// The deserialized type (remote variant) can only be used on the thread it was
+// deserialized on and it will stop working if the thread it was sent from is
+// shutdown (consumers should make sure that the originating thread is kept
+// alive for the necessary time).
+class QuotaObject {
+ public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  CanonicalQuotaObject* AsCanonicalQuotaObject();
+
+  RemoteQuotaObject* AsRemoteQuotaObject();
+
+  // Serialize this QuotaObject. This method works only in the parent process
+  // and only with objects which haven't been previously deserialized.
+  // The serial event target where this method is called should be highly
+  // available, as it will be used to process requests from the remote variant.
+  IPCQuotaObject Serialize(nsIInterfaceRequestor* aCallbacks);
+
+  // Deserialize a QuotaObject. This method works in both the child and parent.
+  // The deserialized QuotaObject can only be used on the calling serial event
+  // target.
+  static RefPtr<QuotaObject> Deserialize(IPCQuotaObject& aQuotaObject);
+
+  virtual const nsAString& Path() const = 0;
+
+  [[nodiscard]] virtual bool MaybeUpdateSize(int64_t aSize, bool aTruncate) = 0;
+
+  virtual bool IncreaseSize(int64_t aDelta) = 0;
+
+  virtual void DisableQuotaCheck() = 0;
+
+  virtual void EnableQuotaCheck() = 0;
+
+ protected:
+  QuotaObject(bool aIsRemote) : mIsRemote(aIsRemote) {}
+
+  virtual ~QuotaObject() = default;
+
+  const bool mIsRemote;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_QUOTAOBJECT_H_
diff --git a/dom/quota/QuotaRequests.cpp b/dom/quota/QuotaRequests.cpp
new file mode 100644
index 0000000000..ee781831c8
--- /dev/null
+++ b/dom/quota/QuotaRequests.cpp
@@ -0,0 +1,288 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QuotaRequests.h"
+
+// Local includes
+#include "ActorsChild.h"
+
+// Global includes
+#include "mozilla/ErrorNames.h"
+#include "mozilla/MacroForEach.h"
+#include "nsDebug.h"
+#include "nsIQuotaCallbacks.h"
+#include "nsISupportsUtils.h"
+#include "nsIVariant.h"
+#include "nsStringFwd.h"
+#include "nscore.h"
+
+namespace mozilla {
+class Runnable;
+}
+
+namespace mozilla::dom::quota {
+
+RequestBase::RequestBase() : mResultCode(NS_OK), mHaveResultOrErrorCode(false) {
+  AssertIsOnOwningThread();
+}
+
+RequestBase::RequestBase(nsIPrincipal* aPrincipal)
+    : mPrincipal(aPrincipal),
+      mResultCode(NS_OK),
+      mHaveResultOrErrorCode(false) {
+  AssertIsOnOwningThread();
+}
+
+#ifdef DEBUG
+
+void RequestBase::AssertIsOnOwningThread() const {
+  NS_ASSERT_OWNINGTHREAD(RequestBase);
+}
+
+#endif  // DEBUG
+
+void RequestBase::SetError(nsresult aRv) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mResultCode == NS_OK);
+  MOZ_ASSERT(!mHaveResultOrErrorCode);
+
+  mResultCode = aRv;
+  mHaveResultOrErrorCode = true;
+
+  FireCallback();
+}
+
+NS_IMPL_CYCLE_COLLECTION_0(RequestBase)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(RequestBase)
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(RequestBase)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(RequestBase)
+
+NS_IMETHODIMP
+RequestBase::GetPrincipal(nsIPrincipal** aPrincipal) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aPrincipal);
+
+  NS_IF_ADDREF(*aPrincipal = mPrincipal);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+RequestBase::GetResultCode(nsresult* aResultCode) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aResultCode);
+
+  if (!mHaveResultOrErrorCode) {
+    return NS_ERROR_FAILURE;
+  }
+
+  *aResultCode = mResultCode;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+RequestBase::GetResultName(nsACString& aResultName) {
+  AssertIsOnOwningThread();
+
+  if (!mHaveResultOrErrorCode) {
+    return NS_ERROR_FAILURE;
+  }
+
+  mozilla::GetErrorName(mResultCode, aResultName);
+  return NS_OK;
+}
+
+UsageRequest::UsageRequest(nsIQuotaUsageCallback* aCallback)
+    : mCallback(aCallback), mBackgroundActor(nullptr), mCanceled(false) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aCallback);
+}
+
+UsageRequest::UsageRequest(nsIPrincipal* aPrincipal,
+                           nsIQuotaUsageCallback* aCallback)
+    : RequestBase(aPrincipal),
+      mCallback(aCallback),
+      mBackgroundActor(nullptr),
+      mCanceled(false) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(aCallback);
+}
+
+UsageRequest::~UsageRequest() { AssertIsOnOwningThread(); }
+
+void UsageRequest::SetBackgroundActor(
+    QuotaUsageRequestChild* aBackgroundActor) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aBackgroundActor);
+  MOZ_ASSERT(!mBackgroundActor);
+
+  mBackgroundActor = aBackgroundActor;
+
+  if (mCanceled) {
+    mBackgroundActor->SendCancel();
+  }
+}
+
+void UsageRequest::SetResult(nsIVariant* aResult) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aResult);
+  MOZ_ASSERT(!mHaveResultOrErrorCode);
+
+  mResult = aResult;
+
+  mHaveResultOrErrorCode = true;
+
+  FireCallback();
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(UsageRequest, RequestBase, mCallback)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(UsageRequest)
+  NS_INTERFACE_MAP_ENTRY(nsIQuotaUsageRequest)
+NS_INTERFACE_MAP_END_INHERITING(RequestBase)
+
+NS_IMPL_ADDREF_INHERITED(UsageRequest, RequestBase)
+NS_IMPL_RELEASE_INHERITED(UsageRequest, RequestBase)
+
+NS_IMETHODIMP
+UsageRequest::GetResult(nsIVariant** aResult) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aResult);
+
+  if (!mHaveResultOrErrorCode) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NS_IF_ADDREF(*aResult = mResult);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageRequest::GetCallback(nsIQuotaUsageCallback** aCallback) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aCallback);
+
+  NS_IF_ADDREF(*aCallback = mCallback);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageRequest::SetCallback(nsIQuotaUsageCallback* aCallback) {
+  AssertIsOnOwningThread();
+
+  mCallback = aCallback;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageRequest::Cancel() {
+  AssertIsOnOwningThread();
+
+  if (mCanceled) {
+    NS_WARNING("Canceled more than once?!");
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  if (mBackgroundActor) {
+    mBackgroundActor->SendCancel();
+  }
+
+  mCanceled = true;
+
+  return NS_OK;
+}
+
+void UsageRequest::FireCallback() {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(mCallback);
+
+  mCallback->OnUsageResult(this);
+
+  // Clean up.
+  mCallback = nullptr;
+}
+
+Request::Request() { AssertIsOnOwningThread(); }
+
+Request::Request(nsIPrincipal* aPrincipal) : RequestBase(aPrincipal) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aPrincipal);
+}
+
+Request::Request(nsIQuotaCallback* aCallback) : mCallback(aCallback) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aCallback);
+}
+
+Request::~Request() { AssertIsOnOwningThread(); }
+
+void Request::SetResult(nsIVariant* aResult) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aResult);
+  MOZ_ASSERT(!mHaveResultOrErrorCode);
+
+  mResult = aResult;
+
+  mHaveResultOrErrorCode = true;
+
+  FireCallback();
+}
+
+NS_IMETHODIMP
+Request::GetResult(nsIVariant** aResult) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aResult);
+
+  if (!mHaveResultOrErrorCode) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NS_IF_ADDREF(*aResult = mResult);
+  return NS_OK;
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(Request, RequestBase, mCallback, mResult)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(Request)
+  NS_INTERFACE_MAP_ENTRY(nsIQuotaRequest)
+NS_INTERFACE_MAP_END_INHERITING(RequestBase)
+
+NS_IMPL_ADDREF_INHERITED(mozilla::dom::quota::Request, RequestBase)
+NS_IMPL_RELEASE_INHERITED(mozilla::dom::quota::Request, RequestBase)
+
+NS_IMETHODIMP
+Request::GetCallback(nsIQuotaCallback** aCallback) {
+  AssertIsOnOwningThread();
+  MOZ_ASSERT(aCallback);
+
+  NS_IF_ADDREF(*aCallback = mCallback);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+Request::SetCallback(nsIQuotaCallback* aCallback) {
+  AssertIsOnOwningThread();
+
+  mCallback = aCallback;
+  return NS_OK;
+}
+
+void Request::FireCallback() {
+  AssertIsOnOwningThread();
+
+  if (mCallback) {
+    mCallback->OnComplete(this);
+
+    // Clean up.
+    mCallback = nullptr;
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/QuotaRequests.h b/dom/quota/QuotaRequests.h
new file mode 100644
index 0000000000..7cfa69ae6d
--- /dev/null
+++ b/dom/quota/QuotaRequests.h
@@ -0,0 +1,121 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_UsageRequest_h
+#define mozilla_dom_quota_UsageRequest_h
+
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/Assertions.h"
+#include "nsCOMPtr.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsIPrincipal.h"
+#include "nsIQuotaRequests.h"
+#include "nsISupports.h"
+
+class nsIQuotaCallback;
+class nsIQuotaUsageCallback;
+class nsIVariant;
+
+namespace mozilla::dom::quota {
+
+class QuotaUsageRequestChild;
+
+class RequestBase : public nsIQuotaRequestBase {
+ protected:
+  nsCOMPtr<nsIPrincipal> mPrincipal;
+
+  nsresult mResultCode;
+  bool mHaveResultOrErrorCode;
+
+ public:
+  void AssertIsOnOwningThread() const
+#ifdef DEBUG
+      ;
+#else
+  {
+  }
+#endif
+
+  void SetError(nsresult aRv);
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_NSIQUOTAREQUESTBASE
+  NS_DECL_CYCLE_COLLECTION_CLASS(RequestBase)
+
+ protected:
+  RequestBase();
+
+  RequestBase(nsIPrincipal* aPrincipal);
+
+  virtual ~RequestBase() { AssertIsOnOwningThread(); }
+
+  virtual void FireCallback() = 0;
+};
+
+class UsageRequest final : public RequestBase, public nsIQuotaUsageRequest {
+  nsCOMPtr<nsIQuotaUsageCallback> mCallback;
+
+  nsCOMPtr<nsIVariant> mResult;
+
+  QuotaUsageRequestChild* mBackgroundActor;
+
+  bool mCanceled;
+
+ public:
+  explicit UsageRequest(nsIQuotaUsageCallback* aCallback);
+
+  UsageRequest(nsIPrincipal* aPrincipal, nsIQuotaUsageCallback* aCallback);
+
+  void SetBackgroundActor(QuotaUsageRequestChild* aBackgroundActor);
+
+  void ClearBackgroundActor() {
+    AssertIsOnOwningThread();
+
+    mBackgroundActor = nullptr;
+  }
+
+  void SetResult(nsIVariant* aResult);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_FORWARD_NSIQUOTAREQUESTBASE(RequestBase::)
+  NS_DECL_NSIQUOTAUSAGEREQUEST
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(UsageRequest, RequestBase)
+
+ private:
+  ~UsageRequest();
+
+  virtual void FireCallback() override;
+};
+
+class Request final : public RequestBase, public nsIQuotaRequest {
+  nsCOMPtr<nsIQuotaCallback> mCallback;
+
+  nsCOMPtr<nsIVariant> mResult;
+
+ public:
+  Request();
+
+  explicit Request(nsIPrincipal* aPrincipal);
+
+  explicit Request(nsIQuotaCallback* aCallback);
+
+  void SetResult(nsIVariant* aResult);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_FORWARD_NSIQUOTAREQUESTBASE(RequestBase::)
+  NS_DECL_NSIQUOTAREQUEST
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(Request, RequestBase)
+
+ private:
+  ~Request();
+
+  virtual void FireCallback() override;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_UsageRequest_h
diff --git a/dom/quota/QuotaResults.cpp b/dom/quota/QuotaResults.cpp
new file mode 100644
index 0000000000..2b715efa22
--- /dev/null
+++ b/dom/quota/QuotaResults.cpp
@@ -0,0 +1,144 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QuotaResults.h"
+
+#include "ErrorList.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/MacroForEach.h"
+#include "nscore.h"
+
+namespace mozilla::dom::quota {
+
+FullOriginMetadataResult::FullOriginMetadataResult(
+    const FullOriginMetadata& aFullOriginMetadata)
+    : mFullOriginMetadata(aFullOriginMetadata) {}
+
+NS_IMPL_ISUPPORTS(FullOriginMetadataResult, nsIQuotaFullOriginMetadataResult)
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetSuffix(nsACString& aSuffix) {
+  aSuffix = mFullOriginMetadata.mSuffix;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetGroup(nsACString& aGroup) {
+  aGroup = mFullOriginMetadata.mGroup;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetOrigin(nsACString& aOrigin) {
+  aOrigin = mFullOriginMetadata.mOrigin;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetPersistenceType(nsACString& aPersistenceType) {
+  aPersistenceType =
+      PersistenceTypeToString(mFullOriginMetadata.mPersistenceType);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetPersisted(bool* aPersisted) {
+  MOZ_ASSERT(aPersisted);
+
+  *aPersisted = mFullOriginMetadata.mPersisted;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+FullOriginMetadataResult::GetLastAccessTime(int64_t* aLastAccessTime) {
+  MOZ_ASSERT(aLastAccessTime);
+
+  *aLastAccessTime = mFullOriginMetadata.mLastAccessTime;
+  return NS_OK;
+}
+
+UsageResult::UsageResult(const nsACString& aOrigin, bool aPersisted,
+                         uint64_t aUsage, uint64_t aLastAccessed)
+    : mOrigin(aOrigin),
+      mUsage(aUsage),
+      mPersisted(aPersisted),
+      mLastAccessed(aLastAccessed) {}
+
+NS_IMPL_ISUPPORTS(UsageResult, nsIQuotaUsageResult)
+
+NS_IMETHODIMP
+UsageResult::GetOrigin(nsACString& aOrigin) {
+  aOrigin = mOrigin;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageResult::GetPersisted(bool* aPersisted) {
+  MOZ_ASSERT(aPersisted);
+
+  *aPersisted = mPersisted;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageResult::GetUsage(uint64_t* aUsage) {
+  MOZ_ASSERT(aUsage);
+
+  *aUsage = mUsage;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UsageResult::GetLastAccessed(uint64_t* aLastAccessed) {
+  MOZ_ASSERT(aLastAccessed);
+
+  *aLastAccessed = mLastAccessed;
+  return NS_OK;
+}
+
+OriginUsageResult::OriginUsageResult(uint64_t aUsage, uint64_t aFileUsage)
+    : mUsage(aUsage), mFileUsage(aFileUsage) {}
+
+NS_IMPL_ISUPPORTS(OriginUsageResult, nsIQuotaOriginUsageResult)
+
+NS_IMETHODIMP
+OriginUsageResult::GetUsage(uint64_t* aUsage) {
+  MOZ_ASSERT(aUsage);
+
+  *aUsage = mUsage;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+OriginUsageResult::GetFileUsage(uint64_t* aFileUsage) {
+  MOZ_ASSERT(aFileUsage);
+
+  *aFileUsage = mFileUsage;
+  return NS_OK;
+}
+
+EstimateResult::EstimateResult(uint64_t aUsage, uint64_t aLimit)
+    : mUsage(aUsage), mLimit(aLimit) {}
+
+NS_IMPL_ISUPPORTS(EstimateResult, nsIQuotaEstimateResult)
+
+NS_IMETHODIMP
+EstimateResult::GetUsage(uint64_t* aUsage) {
+  MOZ_ASSERT(aUsage);
+
+  *aUsage = mUsage;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+EstimateResult::GetLimit(uint64_t* aLimit) {
+  MOZ_ASSERT(aLimit);
+
+  *aLimit = mLimit;
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/QuotaResults.h b/dom/quota/QuotaResults.h
new file mode 100644
index 0000000000..e60eff4043
--- /dev/null
+++ b/dom/quota/QuotaResults.h
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_QuotaResults_h
+#define mozilla_dom_quota_QuotaResults_h
+
+#include <cstdint>
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "nsIQuotaResults.h"
+#include "nsISupports.h"
+#include "nsString.h"
+
+namespace mozilla::dom::quota {
+
+class FullOriginMetadataResult : public nsIQuotaFullOriginMetadataResult {
+  const FullOriginMetadata mFullOriginMetadata;
+
+ public:
+  explicit FullOriginMetadataResult(
+      const FullOriginMetadata& aFullOriginMetadata);
+
+ private:
+  virtual ~FullOriginMetadataResult() = default;
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIQUOTAFULLORIGINMETADATARESULT
+};
+
+class UsageResult : public nsIQuotaUsageResult {
+  nsCString mOrigin;
+  uint64_t mUsage;
+  bool mPersisted;
+  uint64_t mLastAccessed;
+
+ public:
+  UsageResult(const nsACString& aOrigin, bool aPersisted, uint64_t aUsage,
+              uint64_t aLastAccessed);
+
+ private:
+  virtual ~UsageResult() = default;
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIQUOTAUSAGERESULT
+};
+
+class OriginUsageResult : public nsIQuotaOriginUsageResult {
+  uint64_t mUsage;
+  uint64_t mFileUsage;
+
+ public:
+  OriginUsageResult(uint64_t aUsage, uint64_t aFileUsage);
+
+ private:
+  virtual ~OriginUsageResult() = default;
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIQUOTAORIGINUSAGERESULT
+};
+
+class EstimateResult : public nsIQuotaEstimateResult {
+  uint64_t mUsage;
+  uint64_t mLimit;
+
+ public:
+  EstimateResult(uint64_t aUsage, uint64_t aLimit);
+
+ private:
+  virtual ~EstimateResult() = default;
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIQUOTAESTIMATERESULT
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_QuotaResults_h
diff --git a/dom/quota/RemoteQuotaObject.cpp b/dom/quota/RemoteQuotaObject.cpp
new file mode 100644
index 0000000000..3fa3370fc1
--- /dev/null
+++ b/dom/quota/RemoteQuotaObject.cpp
@@ -0,0 +1,65 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "RemoteQuotaObject.h"
+
+#include "mozilla/dom/quota/RemoteQuotaObjectChild.h"
+#include "mozilla/ipc/BackgroundParent.h"
+
+namespace mozilla::dom::quota {
+
+RemoteQuotaObject::RemoteQuotaObject(RefPtr<RemoteQuotaObjectChild> aActor)
+    : QuotaObject(/* aIsRemote */ true), mActor(std::move(aActor)) {
+  MOZ_COUNT_CTOR(RemoteQuotaObject);
+
+  mActor->SetRemoteQuotaObject(this);
+}
+
+RemoteQuotaObject::~RemoteQuotaObject() {
+  MOZ_COUNT_DTOR(RemoteQuotaObject);
+
+  Close();
+}
+
+void RemoteQuotaObject::ClearActor() {
+  MOZ_ASSERT(mActor);
+
+  mActor = nullptr;
+}
+
+void RemoteQuotaObject::Close() {
+  if (!mActor) {
+    return;
+  }
+
+  MOZ_ASSERT(mActor->GetActorEventTarget()->IsOnCurrentThread());
+
+  mActor->Close();
+  MOZ_ASSERT(!mActor);
+}
+
+const nsAString& RemoteQuotaObject::Path() const { return EmptyString(); }
+
+bool RemoteQuotaObject::MaybeUpdateSize(int64_t aSize, bool aTruncate) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(!mozilla::ipc::IsOnBackgroundThread());
+  MOZ_ASSERT(!GetCurrentThreadWorkerPrivate());
+
+  if (!mActor) {
+    return false;
+  }
+
+  MOZ_ASSERT(mActor->GetActorEventTarget()->IsOnCurrentThread());
+
+  bool result;
+  if (!mActor->SendMaybeUpdateSize(aSize, aTruncate, &result)) {
+    return false;
+  }
+
+  return result;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/RemoteQuotaObject.h b/dom/quota/RemoteQuotaObject.h
new file mode 100644
index 0000000000..48ae0c51f3
--- /dev/null
+++ b/dom/quota/RemoteQuotaObject.h
@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_REMOTEQUOTAOBJECT_H_
+#define DOM_QUOTA_REMOTEQUOTAOBJECT_H_
+
+#include "mozilla/dom/quota/QuotaObject.h"
+
+namespace mozilla::dom::quota {
+
+class RemoteQuotaObjectChild;
+
+// This object can only be used on the thread which it was created on
+class RemoteQuotaObject final : public QuotaObject {
+ public:
+  explicit RemoteQuotaObject(RefPtr<RemoteQuotaObjectChild> aActor);
+
+  NS_INLINE_DECL_REFCOUNTING_ONEVENTTARGET(RemoteQuotaObject, override)
+
+  void ClearActor();
+
+  void Close();
+
+  const nsAString& Path() const override;
+
+  // This method should never be called on the main thread or the PBackground
+  // thread or a DOM worker thread (It does sync IPC).
+  [[nodiscard]] bool MaybeUpdateSize(int64_t aSize, bool aTruncate) override;
+
+  bool IncreaseSize(int64_t aDelta) override { return false; }
+
+  void DisableQuotaCheck() override {}
+
+  void EnableQuotaCheck() override {}
+
+ private:
+  ~RemoteQuotaObject();
+
+  RefPtr<RemoteQuotaObjectChild> mActor;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_REMOTEQUOTAOBJECT_H_
diff --git a/dom/quota/RemoteQuotaObjectChild.cpp b/dom/quota/RemoteQuotaObjectChild.cpp
new file mode 100644
index 0000000000..2ea0d64978
--- /dev/null
+++ b/dom/quota/RemoteQuotaObjectChild.cpp
@@ -0,0 +1,33 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "RemoteQuotaObjectChild.h"
+
+#include "RemoteQuotaObject.h"
+
+namespace mozilla::dom::quota {
+
+RemoteQuotaObjectChild::RemoteQuotaObjectChild()
+    : mRemoteQuotaObject(nullptr) {}
+
+RemoteQuotaObjectChild::~RemoteQuotaObjectChild() = default;
+
+void RemoteQuotaObjectChild::SetRemoteQuotaObject(
+    RemoteQuotaObject* aRemoteQuotaObject) {
+  MOZ_ASSERT(aRemoteQuotaObject);
+  MOZ_ASSERT(!mRemoteQuotaObject);
+
+  mRemoteQuotaObject = aRemoteQuotaObject;
+}
+
+void RemoteQuotaObjectChild::ActorDestroy(ActorDestroyReason aWhy) {
+  if (mRemoteQuotaObject) {
+    mRemoteQuotaObject->ClearActor();
+    mRemoteQuotaObject = nullptr;
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/RemoteQuotaObjectChild.h b/dom/quota/RemoteQuotaObjectChild.h
new file mode 100644
index 0000000000..a052a3748a
--- /dev/null
+++ b/dom/quota/RemoteQuotaObjectChild.h
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_REMOTEQUOTAOBJECTCHILD_H_
+#define DOM_QUOTA_REMOTEQUOTAOBJECTCHILD_H_
+
+#include "mozilla/dom/quota/PRemoteQuotaObjectChild.h"
+
+namespace mozilla::dom::quota {
+
+class RemoteQuotaObject;
+
+class RemoteQuotaObjectChild : public PRemoteQuotaObjectChild {
+ public:
+  RemoteQuotaObjectChild();
+
+  NS_INLINE_DECL_REFCOUNTING_ONEVENTTARGET(RemoteQuotaObjectChild, override)
+
+  void SetRemoteQuotaObject(RemoteQuotaObject* aRemoteQuotaObject);
+
+  void ActorDestroy(ActorDestroyReason aWhy) override;
+
+ private:
+  virtual ~RemoteQuotaObjectChild();
+
+  // The weak reference is cleared in ActorDestroy.
+  RemoteQuotaObject* MOZ_NON_OWNING_REF mRemoteQuotaObject;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_REMOTEQUOTAOBJECTCHILD_H_
diff --git a/dom/quota/RemoteQuotaObjectParent.cpp b/dom/quota/RemoteQuotaObjectParent.cpp
new file mode 100644
index 0000000000..2624aa8b58
--- /dev/null
+++ b/dom/quota/RemoteQuotaObjectParent.cpp
@@ -0,0 +1,45 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "RemoteQuotaObjectParent.h"
+
+#include "CanonicalQuotaObject.h"
+#include "mozilla/dom/quota/RemoteQuotaObjectParentTracker.h"
+#include "mozilla/ipc/BackgroundParent.h"
+
+namespace mozilla::dom::quota {
+
+RemoteQuotaObjectParent::RemoteQuotaObjectParent(
+    RefPtr<CanonicalQuotaObject> aCanonicalQuotaObject,
+    nsCOMPtr<RemoteQuotaObjectParentTracker> aTracker)
+    : mCanonicalQuotaObject(std::move(aCanonicalQuotaObject)),
+      mTracker(std::move(aTracker)) {}
+
+RemoteQuotaObjectParent::~RemoteQuotaObjectParent() { MOZ_ASSERT(!CanSend()); }
+
+mozilla::ipc::IPCResult RemoteQuotaObjectParent::RecvMaybeUpdateSize(
+    int64_t aSize, bool aTruncate, bool* aResult) {
+  MOZ_ASSERT(!NS_IsMainThread());
+  MOZ_ASSERT(!mozilla::ipc::IsOnBackgroundThread());
+  MOZ_ASSERT(!GetCurrentThreadWorkerPrivate());
+
+  *aResult = mCanonicalQuotaObject->MaybeUpdateSize(aSize, aTruncate);
+  return IPC_OK();
+}
+
+void RemoteQuotaObjectParent::ActorDestroy(ActorDestroyReason aWhy) {
+  // XXX Check that the child properly used `MaybeUpdateSize` before each
+  // write, so the file size on disk matches mCanonicalQuotaObject::mSize.
+  // If the size doesn't match, do necessary adjustments.
+
+  mCanonicalQuotaObject = nullptr;
+
+  if (mTracker) {
+    mTracker->UnregisterRemoteQuotaObjectParent(WrapNotNullUnchecked(this));
+  }
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/RemoteQuotaObjectParent.h b/dom/quota/RemoteQuotaObjectParent.h
new file mode 100644
index 0000000000..4932e37e64
--- /dev/null
+++ b/dom/quota/RemoteQuotaObjectParent.h
@@ -0,0 +1,39 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_REMOTEQUOTAOBJECTPARENT_H_
+#define DOM_QUOTA_REMOTEQUOTAOBJECTPARENT_H_
+
+#include "mozilla/dom/quota/PRemoteQuotaObjectParent.h"
+
+namespace mozilla::dom::quota {
+
+class CanonicalQuotaObject;
+class RemoteQuotaObjectParentTracker;
+
+class RemoteQuotaObjectParent : public PRemoteQuotaObjectParent {
+ public:
+  RemoteQuotaObjectParent(RefPtr<CanonicalQuotaObject> aCanonicalQuotaObject,
+                          nsCOMPtr<RemoteQuotaObjectParentTracker> aTracker);
+
+  NS_INLINE_DECL_REFCOUNTING_ONEVENTTARGET(RemoteQuotaObjectParent, override)
+
+  mozilla::ipc::IPCResult RecvMaybeUpdateSize(int64_t aSize, bool aTruncate,
+                                              bool* aResult);
+
+  void ActorDestroy(ActorDestroyReason aWhy) override;
+
+ private:
+  virtual ~RemoteQuotaObjectParent();
+
+  RefPtr<CanonicalQuotaObject> mCanonicalQuotaObject;
+
+  nsCOMPtr<RemoteQuotaObjectParentTracker> mTracker;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_REMOTEQUOTAOBJECTPARENT_H_
diff --git a/dom/quota/RemoteQuotaObjectParentTracker.h b/dom/quota/RemoteQuotaObjectParentTracker.h
new file mode 100644
index 0000000000..d712e08c0d
--- /dev/null
+++ b/dom/quota/RemoteQuotaObjectParentTracker.h
@@ -0,0 +1,45 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_H_
+#define DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_H_
+
+#include "mozilla/NotNull.h"
+#include "nsISupports.h"
+
+#define MOZILLA_DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_IID \
+  {                                                          \
+    0x42f96136, 0x5b2b, 0x4487, {                            \
+      0xa4, 0x4e, 0x45, 0x0a, 0x00, 0x8f, 0xc5, 0xd4         \
+    }                                                        \
+  }
+
+namespace mozilla::dom::quota {
+
+class RemoteQuotaObjectParent;
+
+class RemoteQuotaObjectParentTracker : public nsISupports {
+ public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(
+      NS_DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_IID)
+
+  virtual void RegisterRemoteQuotaObjectParent(
+      NotNull<RemoteQuotaObjectParent*> aActor) = 0;
+
+  virtual void UnregisterRemoteQuotaObjectParent(
+      NotNull<RemoteQuotaObjectParent*> aActor) = 0;
+
+ protected:
+  virtual ~RemoteQuotaObjectParentTracker() = default;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(
+    RemoteQuotaObjectParentTracker,
+    MOZILLA_DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_IID)
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_REMOTEQUOTAOBJECTPARENTTRACKER_H_
diff --git a/dom/quota/RemoveParen.h b/dom/quota/RemoveParen.h
new file mode 100644
index 0000000000..4dbc9f129b
--- /dev/null
+++ b/dom/quota/RemoveParen.h
@@ -0,0 +1,18 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_REMOVEPAREN_H_
+#define DOM_QUOTA_REMOVEPAREN_H_
+
+// See
+// https://stackoverflow.com/questions/24481810/how-to-remove-the-enclosing-parentheses-with-macro
+#define MOZ_REMOVE_PAREN(X) MOZ_REMOVE_PAREN_HELPER2(MOZ_REMOVE_PAREN_HELPER X)
+#define MOZ_REMOVE_PAREN_HELPER(...) MOZ_REMOVE_PAREN_HELPER __VA_ARGS__
+#define MOZ_REMOVE_PAREN_HELPER2(...) MOZ_REMOVE_PAREN_HELPER3(__VA_ARGS__)
+#define MOZ_REMOVE_PAREN_HELPER3(...) MOZ_REMOVE_PAREN_HELPER4_##__VA_ARGS__
+#define MOZ_REMOVE_PAREN_HELPER4_MOZ_REMOVE_PAREN_HELPER
+
+#endif  // DOM_QUOTA_REMOVEPAREN_H_
diff --git a/dom/quota/ResultExtensions.h b/dom/quota/ResultExtensions.h
new file mode 100644
index 0000000000..c19bf92661
--- /dev/null
+++ b/dom/quota/ResultExtensions.h
@@ -0,0 +1,160 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_QMRESULTINLINES_H_
+#define DOM_QUOTA_QMRESULTINLINES_H_
+
+#include "nsError.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/dom/QMResult.h"
+#include "mozilla/dom/quota/Config.h"
+#include "mozilla/dom/quota/RemoveParen.h"
+
+#ifdef QM_ERROR_STACKS_ENABLED
+#  include "mozilla/ResultVariant.h"
+#endif
+
+namespace mozilla {
+
+// Allow bool errors to automatically convert to bool values, so MOZ_TRY/QM_TRY
+// can be used in bool returning methods with Result<T, bool> results.
+template <>
+class [[nodiscard]] GenericErrorResult<bool> {
+  bool mErrorValue;
+
+  template <typename V, typename E2>
+  friend class Result;
+
+ public:
+  explicit GenericErrorResult(bool aErrorValue) : mErrorValue(aErrorValue) {
+    MOZ_ASSERT(!aErrorValue);
+  }
+
+  GenericErrorResult(bool aErrorValue, const ErrorPropagationTag&)
+      : GenericErrorResult(aErrorValue) {}
+
+  MOZ_IMPLICIT operator bool() const { return mErrorValue; }
+};
+
+// Allow MOZ_TRY/QM_TRY to handle `bool` values.
+template <typename E = nsresult>
+inline Result<Ok, E> ToResult(bool aValue) {
+  if (aValue) {
+    return Ok();
+  }
+  return Err(ResultTypeTraits<E>::From(NS_ERROR_FAILURE));
+}
+
+constexpr nsresult ToNSResult(nsresult aError) { return aError; }
+
+#ifdef QM_ERROR_STACKS_ENABLED
+
+inline nsresult ToNSResult(const QMResult& aError) { return aError.NSResult(); }
+
+// Allow QMResult errors to use existing stack id and to increase the frame id
+// during error propagation.
+template <>
+class [[nodiscard]] GenericErrorResult<QMResult> {
+  QMResult mErrorValue;
+
+  template <typename V, typename E2>
+  friend class Result;
+
+ public:
+  explicit GenericErrorResult(const QMResult& aErrorValue)
+      : mErrorValue(aErrorValue) {
+    MOZ_ASSERT(NS_FAILED(aErrorValue.NSResult()));
+  }
+
+  explicit GenericErrorResult(QMResult&& aErrorValue)
+      : mErrorValue(std::move(aErrorValue)) {
+    MOZ_ASSERT(NS_FAILED(aErrorValue.NSResult()));
+  }
+
+  explicit GenericErrorResult(const QMResult& aErrorValue,
+                              const ErrorPropagationTag&)
+      : GenericErrorResult(aErrorValue.Propagate()) {}
+
+  explicit GenericErrorResult(QMResult&& aErrorValue,
+                              const ErrorPropagationTag&)
+      : GenericErrorResult(aErrorValue.Propagate()) {}
+
+  operator QMResult() const { return mErrorValue; }
+
+  operator nsresult() const { return mErrorValue.NSResult(); }
+};
+
+template <>
+struct ResultTypeTraits<QMResult> {
+  static QMResult From(nsresult aValue) { return ToQMResult(aValue); }
+
+  static QMResult From(const QMResult& aValue) { return aValue; }
+
+  static QMResult From(QMResult&& aValue) { return std::move(aValue); }
+};
+
+template <typename E>
+inline Result<Ok, E> ToResult(const QMResult& aValue) {
+  if (NS_FAILED(aValue.NSResult())) {
+    return Err(ResultTypeTraits<E>::From(aValue));
+  }
+  return Ok();
+}
+
+template <typename E>
+inline Result<Ok, E> ToResult(QMResult&& aValue) {
+  if (NS_FAILED(aValue.NSResult())) {
+    return Err(ResultTypeTraits<E>::From(aValue));
+  }
+  return Ok();
+}
+#endif
+
+template <typename E = nsresult, typename V, typename E2>
+inline Result<V, E> ToResultTransform(Result<V, E2>&& aValue) {
+  return std::forward<Result<V, E2>>(aValue).mapErr(
+      [](auto&& err) { return ResultTypeTraits<E>::From(err); });
+}
+
+// TODO: Maybe move this to mfbt/ResultExtensions.h
+template <typename R, typename Func, typename... Args>
+Result<R, nsresult> ToResultGet(const Func& aFunc, Args&&... aArgs) {
+  nsresult rv;
+  R res = aFunc(std::forward<Args>(aArgs)..., &rv);
+  if (NS_FAILED(rv)) {
+    return Err(rv);
+  }
+  return res;
+}
+
+}  // namespace mozilla
+
+// TODO: Maybe move this to mfbt/ResultExtensions.h
+#define MOZ_TO_RESULT(expr) ToResult(expr)
+
+#define QM_TO_RESULT(expr) ToResult<QMResult>(expr)
+
+#define QM_TO_RESULT_TRANSFORM(value) ToResultTransform<QMResult>(value)
+
+#define MOZ_TO_RESULT_GET_TYPED(resultType, ...) \
+  ::mozilla::ToResultGet<MOZ_REMOVE_PAREN(resultType)>(__VA_ARGS__)
+
+#define MOZ_TO_RESULT_INVOKE_TYPED(resultType, ...) \
+  ::mozilla::ToResultInvoke<MOZ_REMOVE_PAREN(resultType)>(__VA_ARGS__)
+
+#define QM_TO_RESULT_INVOKE_MEMBER(obj, methodname, ...)                 \
+  ::mozilla::ToResultInvokeMember<QMResult>(                             \
+      (obj), &::mozilla::detail::DerefedType<decltype(obj)>::methodname, \
+      ##__VA_ARGS__)
+
+#define QM_TO_RESULT_INVOKE_MEMBER_TYPED(resultType, obj, methodname, ...) \
+  (::mozilla::ToResultInvoke<resultType, QMResult>(                        \
+      ::std::mem_fn(                                                       \
+          &::mozilla::detail::DerefedType<decltype(obj)>::methodname),     \
+      (obj), ##__VA_ARGS__))
+
+#endif
diff --git a/dom/quota/ScopedLogExtraInfo.cpp b/dom/quota/ScopedLogExtraInfo.cpp
new file mode 100644
index 0000000000..c3ad5e04e1
--- /dev/null
+++ b/dom/quota/ScopedLogExtraInfo.cpp
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ScopedLogExtraInfo.h"
+
+namespace mozilla::dom::quota {
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+MOZ_THREAD_LOCAL(const nsACString*) ScopedLogExtraInfo::sQueryValue;
+MOZ_THREAD_LOCAL(const nsACString*) ScopedLogExtraInfo::sContextValue;
+
+/* static */
+auto ScopedLogExtraInfo::FindSlot(const char* aTag) {
+  // XXX For now, don't use a real map but just allow the known tag values.
+
+  if (aTag == kTagQuery) {
+    return &sQueryValue;
+  }
+
+  if (aTag == kTagContext) {
+    return &sContextValue;
+  }
+
+  MOZ_CRASH("Unknown tag!");
+}
+
+ScopedLogExtraInfo::~ScopedLogExtraInfo() {
+  if (mTag) {
+    MOZ_ASSERT(&mCurrentValue == FindSlot(mTag)->get(),
+               "Bad scoping of ScopedLogExtraInfo, must not be interleaved!");
+
+    FindSlot(mTag)->set(mPreviousValue);
+  }
+}
+
+ScopedLogExtraInfo::ScopedLogExtraInfo(ScopedLogExtraInfo&& aOther)
+    : mTag(aOther.mTag),
+      mPreviousValue(aOther.mPreviousValue),
+      mCurrentValue(std::move(aOther.mCurrentValue)) {
+  aOther.mTag = nullptr;
+  FindSlot(mTag)->set(&mCurrentValue);
+}
+
+/* static */ ScopedLogExtraInfo::ScopedLogExtraInfoMap
+ScopedLogExtraInfo::GetExtraInfoMap() {
+  // This could be done in a cheaper way, but this is never called on a hot
+  // path, so we anticipate using a real map inside here to make use simpler for
+  // the caller(s).
+
+  ScopedLogExtraInfoMap map;
+  if (XRE_IsParentProcess()) {
+    if (sQueryValue.get()) {
+      map.emplace(kTagQuery, sQueryValue.get());
+    }
+
+    if (sContextValue.get()) {
+      map.emplace(kTagContext, sContextValue.get());
+    }
+  }
+  return map;
+}
+
+/* static */ void ScopedLogExtraInfo::Initialize() {
+  MOZ_ALWAYS_TRUE(sQueryValue.init());
+  MOZ_ALWAYS_TRUE(sContextValue.init());
+}
+
+void ScopedLogExtraInfo::AddInfo() {
+  auto* slot = FindSlot(mTag);
+  MOZ_ASSERT(slot);
+  mPreviousValue = slot->get();
+
+  slot->set(&mCurrentValue);
+}
+#endif
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/ScopedLogExtraInfo.h b/dom/quota/ScopedLogExtraInfo.h
new file mode 100644
index 0000000000..d8412ae5b1
--- /dev/null
+++ b/dom/quota/ScopedLogExtraInfo.h
@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_
+#define DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_
+
+#include "mozilla/dom/quota/Config.h"
+
+#include <map>
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/ThreadLocal.h"
+#include "nsString.h"
+#include "nsXULAppAPI.h"
+
+namespace mozilla::dom::quota {
+
+struct MOZ_STACK_CLASS ScopedLogExtraInfo {
+  static constexpr const char kTagQuery[] = "query";
+  static constexpr const char kTagContext[] = "context";
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+ private:
+  static auto FindSlot(const char* aTag);
+
+ public:
+  template <size_t N>
+  ScopedLogExtraInfo(const char (&aTag)[N], const nsACString& aExtraInfo)
+      : mTag{aTag}, mCurrentValue{aExtraInfo} {
+    // Initialize is currently only called in the parent process, we could call
+    // it directly from nsLayoutStatics::Initialize in the content process to
+    // allow use of ScopedLogExtraInfo in that too. The check in GetExtraInfoMap
+    // must be removed then.
+    MOZ_ASSERT(XRE_IsParentProcess());
+
+    AddInfo();
+  }
+
+  ~ScopedLogExtraInfo();
+
+  ScopedLogExtraInfo(ScopedLogExtraInfo&& aOther);
+  ScopedLogExtraInfo& operator=(ScopedLogExtraInfo&& aOther) = delete;
+
+  ScopedLogExtraInfo(const ScopedLogExtraInfo&) = delete;
+  ScopedLogExtraInfo& operator=(const ScopedLogExtraInfo&) = delete;
+
+  using ScopedLogExtraInfoMap = std::map<const char*, const nsACString*>;
+  static ScopedLogExtraInfoMap GetExtraInfoMap();
+
+  static void Initialize();
+
+ private:
+  const char* mTag;
+  const nsACString* mPreviousValue;
+  nsCString mCurrentValue;
+
+  static MOZ_THREAD_LOCAL(const nsACString*) sQueryValue;
+  static MOZ_THREAD_LOCAL(const nsACString*) sContextValue;
+
+  void AddInfo();
+#else
+  template <size_t N>
+  ScopedLogExtraInfo(const char (&aTag)[N], const nsACString& aExtraInfo) {}
+
+  // user-defined to silence unused variable warnings
+  ~ScopedLogExtraInfo() {}
+#endif
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_SCOPEDLOGEXTRAINFO_H_
diff --git a/dom/quota/SerializationHelpers.h b/dom/quota/SerializationHelpers.h
new file mode 100644
index 0000000000..e63e3ef67d
--- /dev/null
+++ b/dom/quota/SerializationHelpers.h
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_SerializationHelpers_h
+#define mozilla_dom_quota_SerializationHelpers_h
+
+#include "ipc/EnumSerializer.h"
+#include "ipc/IPCMessageUtils.h"
+
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "mozilla/dom/quota/PersistenceType.h"
+#include "mozilla/OriginAttributes.h"
+
+namespace IPC {
+
+template <>
+struct ParamTraits<mozilla::dom::quota::PersistenceType>
+    : public ContiguousEnumSerializer<
+          mozilla::dom::quota::PersistenceType,
+          mozilla::dom::quota::PERSISTENCE_TYPE_PERSISTENT,
+          mozilla::dom::quota::PERSISTENCE_TYPE_INVALID> {};
+
+template <>
+struct ParamTraits<mozilla::dom::quota::Client::Type>
+    : public ContiguousEnumSerializer<mozilla::dom::quota::Client::Type,
+                                      mozilla::dom::quota::Client::IDB,
+                                      mozilla::dom::quota::Client::TYPE_MAX> {};
+
+template <>
+struct ParamTraits<mozilla::dom::quota::FullOriginMetadata> {
+  using ParamType = mozilla::dom::quota::FullOriginMetadata;
+
+  static void Write(MessageWriter* aWriter, const ParamType& aParam) {
+    WriteParam(aWriter, aParam.mSuffix);
+    WriteParam(aWriter, aParam.mGroup);
+    WriteParam(aWriter, aParam.mOrigin);
+    WriteParam(aWriter, aParam.mPersistenceType);
+    WriteParam(aWriter, aParam.mPersisted);
+    WriteParam(aWriter, aParam.mLastAccessTime);
+  }
+
+  static bool Read(MessageReader* aReader, ParamType* aResult) {
+    return ReadParam(aReader, &aResult->mSuffix) &&
+           ReadParam(aReader, &aResult->mGroup) &&
+           ReadParam(aReader, &aResult->mOrigin) &&
+           ReadParam(aReader, &aResult->mPersistenceType) &&
+           ReadParam(aReader, &aResult->mPersisted) &&
+           ReadParam(aReader, &aResult->mLastAccessTime);
+  }
+};
+
+template <>
+struct ParamTraits<mozilla::OriginAttributesPattern> {
+  typedef mozilla::OriginAttributesPattern paramType;
+
+  static void Write(MessageWriter* aWriter, const paramType& aParam) {
+    WriteParam(aWriter, aParam.mFirstPartyDomain);
+    WriteParam(aWriter, aParam.mInIsolatedMozBrowser);
+    WriteParam(aWriter, aParam.mPrivateBrowsingId);
+    WriteParam(aWriter, aParam.mUserContextId);
+    WriteParam(aWriter, aParam.mGeckoViewSessionContextId);
+  }
+
+  static bool Read(MessageReader* aReader, paramType* aResult) {
+    return ReadParam(aReader, &aResult->mFirstPartyDomain) &&
+           ReadParam(aReader, &aResult->mInIsolatedMozBrowser) &&
+           ReadParam(aReader, &aResult->mPrivateBrowsingId) &&
+           ReadParam(aReader, &aResult->mUserContextId) &&
+           ReadParam(aReader, &aResult->mGeckoViewSessionContextId);
+  }
+};
+
+}  // namespace IPC
+
+#endif  // mozilla_dom_quota_SerializationHelpers_h
diff --git a/dom/quota/StorageHelpers.cpp b/dom/quota/StorageHelpers.cpp
new file mode 100644
index 0000000000..84cd806297
--- /dev/null
+++ b/dom/quota/StorageHelpers.cpp
@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/StorageHelpers.h"
+
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+
+namespace mozilla::dom::quota {
+
+AutoDatabaseAttacher::AutoDatabaseAttacher(
+    nsCOMPtr<mozIStorageConnection> aConnection,
+    nsCOMPtr<nsIFile> aDatabaseFile, const nsLiteralCString& aSchemaName)
+    : mConnection(std::move(aConnection)),
+      mDatabaseFile(std::move(aDatabaseFile)),
+      mSchemaName(aSchemaName),
+      mAttached(false) {}
+
+AutoDatabaseAttacher::~AutoDatabaseAttacher() {
+  if (mAttached) {
+    QM_WARNONLY_TRY(MOZ_TO_RESULT(Detach()));
+  }
+}
+
+nsresult AutoDatabaseAttacher::Attach() {
+  MOZ_ASSERT(mConnection);
+  MOZ_ASSERT(mDatabaseFile);
+  MOZ_ASSERT(!mAttached);
+
+#ifdef DEBUG
+  {
+    QM_TRY_INSPECT(const bool& exists,
+                   MOZ_TO_RESULT_INVOKE_MEMBER(mDatabaseFile, Exists));
+
+    MOZ_ASSERT(exists);
+  }
+#endif
+
+  QM_TRY_INSPECT(const auto& path, MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+                                       nsString, mDatabaseFile, GetPath));
+
+  QM_TRY_INSPECT(
+      const auto& stmt,
+      MOZ_TO_RESULT_INVOKE_MEMBER_TYPED(
+          nsCOMPtr<mozIStorageStatement>, mConnection, CreateStatement,
+          "ATTACH DATABASE :path AS "_ns + mSchemaName + ";"_ns));
+
+  QM_TRY(MOZ_TO_RESULT(stmt->BindStringByName("path"_ns, path)));
+  QM_TRY(MOZ_TO_RESULT(stmt->Execute()));
+
+  mAttached = true;
+
+  return NS_OK;
+}
+
+nsresult AutoDatabaseAttacher::Detach() {
+  MOZ_ASSERT(mConnection);
+  MOZ_ASSERT(mAttached);
+
+  QM_TRY(MOZ_TO_RESULT(
+      mConnection->ExecuteSimpleSQL("DETACH DATABASE "_ns + mSchemaName)));
+
+  mAttached = false;
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/StorageHelpers.h b/dom/quota/StorageHelpers.h
new file mode 100644
index 0000000000..f1830db360
--- /dev/null
+++ b/dom/quota/StorageHelpers.h
@@ -0,0 +1,54 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_QUOTADATABASEHELPER_H
+#define DOM_QUOTA_QUOTADATABASEHELPER_H
+
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "mozIStorageConnection.h"
+#include "nsCOMPtr.h"
+#include "nsString.h"
+
+namespace mozilla::dom::quota {
+
+/**
+ * This class provides a RAII wrap of attaching and detaching database
+ * in a given C++ scope. It is guaranteed that an attached database will
+ * be detached even if you have an exception or return early.
+ *
+ * @param aConnection
+ *        The connection to attach a database to.
+ * @param aDatabaseFile
+ *        The database file to attach.
+ * @param aSchemaName
+ *        The schema-name. Can be any string literal which is supported by the
+ *        underlying database. For more details about schema-name, see
+ *        https://www.sqlite.org/lang_attach.html
+ */
+class MOZ_STACK_CLASS AutoDatabaseAttacher final {
+ public:
+  explicit AutoDatabaseAttacher(nsCOMPtr<mozIStorageConnection> aConnection,
+                                nsCOMPtr<nsIFile> aDatabaseFile,
+                                const nsLiteralCString& aSchemaName);
+
+  ~AutoDatabaseAttacher();
+
+  AutoDatabaseAttacher() = delete;
+
+  [[nodiscard]] nsresult Attach();
+
+  [[nodiscard]] nsresult Detach();
+
+ private:
+  nsCOMPtr<mozIStorageConnection> mConnection;
+  nsCOMPtr<nsIFile> mDatabaseFile;
+  const nsLiteralCString mSchemaName;
+  bool mAttached;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_QUOTADATABASEHELPER_H
diff --git a/dom/quota/StorageManager.cpp b/dom/quota/StorageManager.cpp
new file mode 100644
index 0000000000..bf05265bc0
--- /dev/null
+++ b/dom/quota/StorageManager.cpp
@@ -0,0 +1,808 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "StorageManager.h"
+#include "fs/FileSystemRequestHandler.h"
+
+#include <cstdint>
+#include <cstdlib>
+#include <utility>
+#include "ErrorList.h"
+#include "fs/FileSystemRequestHandler.h"
+#include "MainThreadUtils.h"
+#include "js/CallArgs.h"
+#include "js/TypeDecls.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/ErrorResult.h"
+#include "mozilla/MacroForEach.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TelemetryScalarEnums.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/FileSystemManager.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/PromiseWorkerProxy.h"
+#include "mozilla/dom/StorageManagerBinding.h"
+#include "mozilla/dom/WorkerCommon.h"
+#include "mozilla/dom/WorkerPrivate.h"
+#include "mozilla/dom/WorkerRunnable.h"
+#include "mozilla/dom/WorkerStatus.h"
+#include "mozilla/dom/quota/QuotaManagerService.h"
+#include "nsContentPermissionHelper.h"
+#include "nsContentUtils.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsIGlobalObject.h"
+#include "nsIPrincipal.h"
+#include "nsIQuotaCallbacks.h"
+#include "nsIQuotaManagerService.h"
+#include "nsIQuotaRequests.h"
+#include "nsIQuotaResults.h"
+#include "nsIVariant.h"
+#include "nsLiteralString.h"
+#include "nsPIDOMWindow.h"
+#include "nsString.h"
+#include "nsStringFlags.h"
+#include "nsTLiteralString.h"
+#include "nscore.h"
+
+class JSObject;
+struct JSContext;
+struct nsID;
+
+namespace mozilla {
+class Runnable;
+}
+
+using namespace mozilla::dom::quota;
+
+namespace mozilla::dom {
+
+namespace {
+
+// This class is used to get quota usage, request persist and check persisted
+// status callbacks.
+class RequestResolver final : public nsIQuotaCallback {
+ public:
+  enum Type { Estimate, Persist, Persisted };
+
+ private:
+  class FinishWorkerRunnable;
+
+  // If this resolver was created for a window then mPromise must be non-null.
+  // Otherwise mProxy must be non-null.
+  RefPtr<Promise> mPromise;
+  RefPtr<PromiseWorkerProxy> mProxy;
+
+  nsresult mResultCode;
+  StorageEstimate mStorageEstimate;
+  const Type mType;
+  bool mPersisted;
+
+ public:
+  RequestResolver(Type aType, Promise* aPromise)
+      : mPromise(aPromise),
+        mResultCode(NS_OK),
+        mType(aType),
+        mPersisted(false) {
+    MOZ_ASSERT(NS_IsMainThread());
+    MOZ_ASSERT(aPromise);
+  }
+
+  RequestResolver(Type aType, PromiseWorkerProxy* aProxy)
+      : mProxy(aProxy), mResultCode(NS_OK), mType(aType), mPersisted(false) {
+    MOZ_ASSERT(NS_IsMainThread());
+    MOZ_ASSERT(aProxy);
+  }
+
+  void ResolveOrReject();
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIQUOTACALLBACK
+
+ private:
+  ~RequestResolver() = default;
+
+  nsresult GetStorageEstimate(nsIVariant* aResult);
+
+  nsresult GetPersisted(nsIVariant* aResult);
+
+  nsresult OnCompleteInternal(nsIQuotaRequest* aRequest);
+
+  nsresult Finish();
+};
+
+// This class is used to return promise on worker thread.
+class RequestResolver::FinishWorkerRunnable final : public WorkerRunnable {
+  RefPtr<RequestResolver> mResolver;
+
+ public:
+  explicit FinishWorkerRunnable(RequestResolver* aResolver)
+      : WorkerRunnable(aResolver->mProxy->GetWorkerPrivate()),
+        mResolver(aResolver) {
+    MOZ_ASSERT(NS_IsMainThread());
+    MOZ_ASSERT(aResolver);
+  }
+
+  bool WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override;
+};
+
+class EstimateWorkerMainThreadRunnable final : public WorkerMainThreadRunnable {
+  RefPtr<PromiseWorkerProxy> mProxy;
+
+ public:
+  EstimateWorkerMainThreadRunnable(WorkerPrivate* aWorkerPrivate,
+                                   PromiseWorkerProxy* aProxy)
+      : WorkerMainThreadRunnable(aWorkerPrivate,
+                                 "StorageManager :: Estimate"_ns),
+        mProxy(aProxy) {
+    MOZ_ASSERT(aWorkerPrivate);
+    aWorkerPrivate->AssertIsOnWorkerThread();
+    MOZ_ASSERT(aProxy);
+  }
+
+  bool MainThreadRun() override;
+};
+
+class PersistedWorkerMainThreadRunnable final
+    : public WorkerMainThreadRunnable {
+  RefPtr<PromiseWorkerProxy> mProxy;
+
+ public:
+  PersistedWorkerMainThreadRunnable(WorkerPrivate* aWorkerPrivate,
+                                    PromiseWorkerProxy* aProxy)
+      : WorkerMainThreadRunnable(aWorkerPrivate,
+                                 "StorageManager :: Persisted"_ns),
+        mProxy(aProxy) {
+    MOZ_ASSERT(aWorkerPrivate);
+    aWorkerPrivate->AssertIsOnWorkerThread();
+    MOZ_ASSERT(aProxy);
+  }
+
+  bool MainThreadRun() override;
+};
+
+/*******************************************************************************
+ * PersistentStoragePermissionRequest
+ ******************************************************************************/
+
+class PersistentStoragePermissionRequest final
+    : public ContentPermissionRequestBase {
+  RefPtr<Promise> mPromise;
+
+ public:
+  PersistentStoragePermissionRequest(nsIPrincipal* aPrincipal,
+                                     nsPIDOMWindowInner* aWindow,
+                                     Promise* aPromise)
+      : ContentPermissionRequestBase(aPrincipal, aWindow,
+                                     "dom.storageManager"_ns,
+                                     "persistent-storage"_ns),
+        mPromise(aPromise) {
+    MOZ_ASSERT(aWindow);
+    MOZ_ASSERT(aPromise);
+  }
+
+  nsresult Start();
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(PersistentStoragePermissionRequest,
+                                           ContentPermissionRequestBase)
+
+  // nsIContentPermissionRequest
+  NS_IMETHOD Cancel(void) override;
+  NS_IMETHOD Allow(JS::Handle<JS::Value> choices) override;
+
+ private:
+  ~PersistentStoragePermissionRequest() = default;
+};
+
+nsresult Estimate(nsIPrincipal* aPrincipal, nsIQuotaCallback* aCallback,
+                  nsIQuotaRequest** aRequest) {
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(aCallback);
+  MOZ_ASSERT(aRequest);
+
+  // Firefox and Quota Manager have always used the schemeless origin group
+  // (https://storage.spec.whatwg.org/#schemeless-origin-group) for quota limit
+  // purposes. This has been to prevent a site/eTLD+1 from claiming more than
+  // its fair share of storage through the use of sub-domains. Because the limit
+  // is at the group level and the usage needs to make sense in the context of
+  // that limit, we also expose the group usage. Bug 1374970 reflects this
+  // reality and bug 1305665 tracks our plan to eliminate our use of groups for
+  // this.
+
+  nsCOMPtr<nsIQuotaManagerService> qms = QuotaManagerService::GetOrCreate();
+  if (NS_WARN_IF(!qms)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIQuotaRequest> request;
+  nsresult rv = qms->Estimate(aPrincipal, getter_AddRefs(request));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  MOZ_ALWAYS_SUCCEEDS(request->SetCallback(aCallback));
+
+  request.forget(aRequest);
+  return NS_OK;
+};
+
+nsresult Persisted(nsIPrincipal* aPrincipal, nsIQuotaCallback* aCallback,
+                   nsIQuotaRequest** aRequest) {
+  MOZ_ASSERT(aPrincipal);
+  MOZ_ASSERT(aCallback);
+  MOZ_ASSERT(aRequest);
+
+  nsCOMPtr<nsIQuotaManagerService> qms = QuotaManagerService::GetOrCreate();
+  if (NS_WARN_IF(!qms)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIQuotaRequest> request;
+  nsresult rv = qms->Persisted(aPrincipal, getter_AddRefs(request));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // All the methods in nsIQuotaManagerService shouldn't synchronously fire
+  // any callbacks when they are being executed. Even when a result is ready,
+  // a new runnable should be dispatched to current thread to fire the callback
+  // asynchronously. It's safe to set the callback after we call Persisted().
+  MOZ_ALWAYS_SUCCEEDS(request->SetCallback(aCallback));
+
+  request.forget(aRequest);
+
+  return NS_OK;
+};
+
+already_AddRefed<Promise> ExecuteOpOnMainOrWorkerThread(
+    nsIGlobalObject* aGlobal, RequestResolver::Type aType, ErrorResult& aRv) {
+  MOZ_ASSERT(aGlobal);
+  MOZ_ASSERT_IF(aType == RequestResolver::Type::Persist, NS_IsMainThread());
+
+  RefPtr<Promise> promise = Promise::Create(aGlobal, aRv);
+  if (NS_WARN_IF(!promise)) {
+    return nullptr;
+  }
+
+  if (NS_IsMainThread()) {
+    nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(aGlobal);
+    if (NS_WARN_IF(!window)) {
+      aRv.Throw(NS_ERROR_FAILURE);
+      return nullptr;
+    }
+
+    nsCOMPtr<Document> doc = window->GetExtantDoc();
+    if (NS_WARN_IF(!doc)) {
+      aRv.Throw(NS_ERROR_FAILURE);
+      return nullptr;
+    }
+
+    nsCOMPtr<nsIPrincipal> principal = doc->NodePrincipal();
+    MOZ_ASSERT(principal);
+
+    // Storage Standard 7. API
+    // If origin is an opaque origin, then reject promise with a TypeError.
+    if (principal->GetIsNullPrincipal()) {
+      switch (aType) {
+        case RequestResolver::Type::Persisted:
+          promise->MaybeRejectWithTypeError(
+              "persisted() called for opaque origin");
+          break;
+        case RequestResolver::Type::Persist:
+          promise->MaybeRejectWithTypeError(
+              "persist() called for opaque origin");
+          break;
+        case RequestResolver::Type::Estimate:
+          promise->MaybeRejectWithTypeError(
+              "estimate() called for opaque origin");
+          break;
+      }
+
+      return promise.forget();
+    }
+
+    switch (aType) {
+      case RequestResolver::Type::Persisted: {
+        RefPtr<RequestResolver> resolver =
+            new RequestResolver(RequestResolver::Type::Persisted, promise);
+
+        RefPtr<nsIQuotaRequest> request;
+        aRv = Persisted(principal, resolver, getter_AddRefs(request));
+
+        break;
+      }
+
+      case RequestResolver::Type::Persist: {
+        RefPtr<PersistentStoragePermissionRequest> request =
+            new PersistentStoragePermissionRequest(principal, window, promise);
+
+        // In private browsing mode, no permission prompt.
+        if (nsContentUtils::IsInPrivateBrowsing(doc)) {
+          aRv = request->Cancel();
+        } else if (!request->CheckPermissionDelegate()) {
+          aRv = request->Cancel();
+        } else {
+          aRv = request->Start();
+        }
+
+        break;
+      }
+
+      case RequestResolver::Type::Estimate: {
+        RefPtr<RequestResolver> resolver =
+            new RequestResolver(RequestResolver::Type::Estimate, promise);
+
+        RefPtr<nsIQuotaRequest> request;
+        aRv = Estimate(principal, resolver, getter_AddRefs(request));
+
+        break;
+      }
+
+      default:
+        MOZ_CRASH("Invalid aRequest type!");
+    }
+
+    if (NS_WARN_IF(aRv.Failed())) {
+      return nullptr;
+    }
+
+    return promise.forget();
+  }
+
+  WorkerPrivate* workerPrivate = GetCurrentThreadWorkerPrivate();
+  MOZ_ASSERT(workerPrivate);
+
+  RefPtr<PromiseWorkerProxy> promiseProxy =
+      PromiseWorkerProxy::Create(workerPrivate, promise);
+  if (NS_WARN_IF(!promiseProxy)) {
+    aRv.Throw(NS_ERROR_FAILURE);
+    return nullptr;
+  }
+
+  switch (aType) {
+    case RequestResolver::Type::Estimate: {
+      RefPtr<EstimateWorkerMainThreadRunnable> runnnable =
+          new EstimateWorkerMainThreadRunnable(promiseProxy->GetWorkerPrivate(),
+                                               promiseProxy);
+      runnnable->Dispatch(Canceling, aRv);
+
+      break;
+    }
+
+    case RequestResolver::Type::Persisted: {
+      RefPtr<PersistedWorkerMainThreadRunnable> runnnable =
+          new PersistedWorkerMainThreadRunnable(
+              promiseProxy->GetWorkerPrivate(), promiseProxy);
+      runnnable->Dispatch(Canceling, aRv);
+
+      break;
+    }
+
+    default:
+      MOZ_CRASH("Invalid aRequest type");
+  }
+
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  return promise.forget();
+};
+
+}  // namespace
+
+/*******************************************************************************
+ * Local class implementations
+ ******************************************************************************/
+
+void RequestResolver::ResolveOrReject() {
+  class MOZ_STACK_CLASS AutoCleanup final {
+    RefPtr<PromiseWorkerProxy> mProxy;
+
+   public:
+    explicit AutoCleanup(PromiseWorkerProxy* aProxy) : mProxy(aProxy) {
+      MOZ_ASSERT(aProxy);
+    }
+
+    ~AutoCleanup() {
+      MOZ_ASSERT(mProxy);
+
+      mProxy->CleanUp();
+    }
+  };
+
+  RefPtr<Promise> promise;
+  Maybe<AutoCleanup> autoCleanup;
+
+  if (mPromise) {
+    promise = mPromise;
+  } else {
+    MOZ_ASSERT(mProxy);
+
+    promise = mProxy->WorkerPromise();
+
+    // Only clean up for worker case.
+    autoCleanup.emplace(mProxy);
+  }
+
+  MOZ_ASSERT(promise);
+
+  if (mType == Type::Estimate) {
+    if (NS_SUCCEEDED(mResultCode)) {
+      promise->MaybeResolve(mStorageEstimate);
+    } else {
+      promise->MaybeRejectWithTypeError(
+          "Internal error while estimating storage usage");
+    }
+
+    return;
+  }
+
+  MOZ_ASSERT(mType == Type::Persist || mType == Type::Persisted);
+
+  if (NS_SUCCEEDED(mResultCode)) {
+    promise->MaybeResolve(mPersisted);
+  } else {
+    promise->MaybeResolve(false);
+  }
+}
+
+NS_IMPL_ISUPPORTS(RequestResolver, nsIQuotaCallback)
+
+nsresult RequestResolver::GetStorageEstimate(nsIVariant* aResult) {
+  MOZ_ASSERT(aResult);
+  MOZ_ASSERT(mType == Type::Estimate);
+
+  MOZ_ASSERT(aResult->GetDataType() == nsIDataType::VTYPE_INTERFACE_IS);
+
+  nsID* iid;
+  nsCOMPtr<nsISupports> supports;
+  nsresult rv = aResult->GetAsInterface(&iid, getter_AddRefs(supports));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  free(iid);
+
+  nsCOMPtr<nsIQuotaEstimateResult> estimateResult = do_QueryInterface(supports);
+  MOZ_ASSERT(estimateResult);
+
+  MOZ_ALWAYS_SUCCEEDS(
+      estimateResult->GetUsage(&mStorageEstimate.mUsage.Construct()));
+
+  MOZ_ALWAYS_SUCCEEDS(
+      estimateResult->GetLimit(&mStorageEstimate.mQuota.Construct()));
+
+  return NS_OK;
+}
+
+nsresult RequestResolver::GetPersisted(nsIVariant* aResult) {
+  MOZ_ASSERT(aResult);
+  MOZ_ASSERT(mType == Type::Persist || mType == Type::Persisted);
+
+#ifdef DEBUG
+  uint16_t dataType = aResult->GetDataType();
+#endif
+
+  if (mType == Type::Persist) {
+    MOZ_ASSERT(dataType == nsIDataType::VTYPE_VOID);
+
+    mPersisted = true;
+    return NS_OK;
+  }
+
+  MOZ_ASSERT(dataType == nsIDataType::VTYPE_BOOL);
+
+  bool persisted;
+  nsresult rv = aResult->GetAsBool(&persisted);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  mPersisted = persisted;
+  return NS_OK;
+}
+
+nsresult RequestResolver::OnCompleteInternal(nsIQuotaRequest* aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+
+  nsresult resultCode;
+  nsresult rv = aRequest->GetResultCode(&resultCode);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (NS_FAILED(resultCode)) {
+    return resultCode;
+  }
+
+  nsCOMPtr<nsIVariant> result;
+  rv = aRequest->GetResult(getter_AddRefs(result));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (mType == Type::Estimate) {
+    rv = GetStorageEstimate(result);
+  } else {
+    MOZ_ASSERT(mType == Type::Persist || mType == Type::Persisted);
+
+    rv = GetPersisted(result);
+  }
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+nsresult RequestResolver::Finish() {
+  // In a main thread request.
+  if (!mProxy) {
+    MOZ_ASSERT(mPromise);
+
+    ResolveOrReject();
+    return NS_OK;
+  }
+
+  {
+    // In a worker thread request.
+    MutexAutoLock lock(mProxy->Lock());
+
+    if (NS_WARN_IF(mProxy->CleanedUp())) {
+      return NS_ERROR_FAILURE;
+    }
+
+    RefPtr<FinishWorkerRunnable> runnable = new FinishWorkerRunnable(this);
+    if (NS_WARN_IF(!runnable->Dispatch())) {
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+RequestResolver::OnComplete(nsIQuotaRequest* aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+
+  mResultCode = OnCompleteInternal(aRequest);
+
+  nsresult rv = Finish();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+bool RequestResolver::FinishWorkerRunnable::WorkerRun(
+    JSContext* aCx, WorkerPrivate* aWorkerPrivate) {
+  MOZ_ASSERT(aCx);
+  MOZ_ASSERT(aWorkerPrivate);
+  aWorkerPrivate->AssertIsOnWorkerThread();
+
+  MOZ_ASSERT(mResolver);
+  mResolver->ResolveOrReject();
+
+  return true;
+}
+
+bool EstimateWorkerMainThreadRunnable::MainThreadRun() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIPrincipal> principal;
+
+  {
+    MutexAutoLock lock(mProxy->Lock());
+    if (mProxy->CleanedUp()) {
+      return true;
+    }
+    principal = mProxy->GetWorkerPrivate()->GetPrincipal();
+  }
+
+  MOZ_ASSERT(principal);
+
+  RefPtr<RequestResolver> resolver =
+      new RequestResolver(RequestResolver::Type::Estimate, mProxy);
+
+  RefPtr<nsIQuotaRequest> request;
+  nsresult rv = Estimate(principal, resolver, getter_AddRefs(request));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return false;
+  }
+
+  return true;
+}
+
+bool PersistedWorkerMainThreadRunnable::MainThreadRun() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIPrincipal> principal;
+
+  {
+    MutexAutoLock lock(mProxy->Lock());
+    if (mProxy->CleanedUp()) {
+      return true;
+    }
+    principal = mProxy->GetWorkerPrivate()->GetPrincipal();
+  }
+
+  MOZ_ASSERT(principal);
+
+  RefPtr<RequestResolver> resolver =
+      new RequestResolver(RequestResolver::Type::Persisted, mProxy);
+
+  RefPtr<nsIQuotaRequest> request;
+  nsresult rv = Persisted(principal, resolver, getter_AddRefs(request));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return false;
+  }
+
+  return true;
+}
+
+nsresult PersistentStoragePermissionRequest::Start() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  PromptResult pr;
+#ifdef MOZ_WIDGET_ANDROID
+  // on Android calling `ShowPrompt` here calls
+  // `nsContentPermissionUtils::AskPermission` once, and a response of
+  // `PromptResult::Pending` calls it again. This results in multiple requests
+  // for storage access, so we check the prompt prefs only to ensure we only
+  // request it once.
+  pr = CheckPromptPrefs();
+#else
+  nsresult rv = ShowPrompt(pr);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+#endif
+  if (pr == PromptResult::Granted) {
+    return Allow(JS::UndefinedHandleValue);
+  }
+  if (pr == PromptResult::Denied) {
+    return Cancel();
+  }
+
+  return nsContentPermissionUtils::AskPermission(this, mWindow);
+}
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(
+    PersistentStoragePermissionRequest, ContentPermissionRequestBase)
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(PersistentStoragePermissionRequest,
+                                   ContentPermissionRequestBase, mPromise)
+
+NS_IMETHODIMP
+PersistentStoragePermissionRequest::Cancel() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(mPromise);
+
+  RefPtr<RequestResolver> resolver =
+      new RequestResolver(RequestResolver::Type::Persisted, mPromise);
+
+  RefPtr<nsIQuotaRequest> request;
+
+  return Persisted(mPrincipal, resolver, getter_AddRefs(request));
+}
+
+NS_IMETHODIMP
+PersistentStoragePermissionRequest::Allow(JS::Handle<JS::Value> aChoices) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  RefPtr<RequestResolver> resolver =
+      new RequestResolver(RequestResolver::Type::Persist, mPromise);
+
+  nsCOMPtr<nsIQuotaManagerService> qms = QuotaManagerService::GetOrCreate();
+  if (NS_WARN_IF(!qms)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  RefPtr<nsIQuotaRequest> request;
+
+  nsresult rv = qms->Persist(mPrincipal, getter_AddRefs(request));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  MOZ_ALWAYS_SUCCEEDS(request->SetCallback(resolver));
+
+  return NS_OK;
+}
+
+/*******************************************************************************
+ * StorageManager
+ ******************************************************************************/
+
+StorageManager::StorageManager(nsIGlobalObject* aGlobal) : mOwner(aGlobal) {
+  MOZ_ASSERT(aGlobal);
+}
+
+StorageManager::~StorageManager() { Shutdown(); }
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(StorageManager)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(StorageManager)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(StorageManager)
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(StorageManager)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(StorageManager)
+  tmp->Shutdown();
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mOwner)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(StorageManager)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOwner)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFileSystemManager)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+void StorageManager::Shutdown() {
+  if (mFileSystemManager) {
+    mFileSystemManager->Shutdown();
+    mFileSystemManager = nullptr;
+  }
+}
+
+already_AddRefed<FileSystemManager> StorageManager::GetFileSystemManager() {
+  if (!mFileSystemManager) {
+    MOZ_ASSERT(mOwner);
+
+    mFileSystemManager = MakeRefPtr<FileSystemManager>(mOwner, this);
+  }
+
+  return do_AddRef(mFileSystemManager);
+}
+
+// WebIDL Boilerplate
+
+JSObject* StorageManager::WrapObject(JSContext* aCx,
+                                     JS::Handle<JSObject*> aGivenProto) {
+  return StorageManager_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+// WebIDL Interface
+
+already_AddRefed<Promise> StorageManager::Persisted(ErrorResult& aRv) {
+  MOZ_ASSERT(mOwner);
+
+  return ExecuteOpOnMainOrWorkerThread(mOwner, RequestResolver::Type::Persisted,
+                                       aRv);
+}
+
+already_AddRefed<Promise> StorageManager::Persist(ErrorResult& aRv) {
+  MOZ_ASSERT(mOwner);
+
+  Telemetry::ScalarAdd(Telemetry::ScalarID::NAVIGATOR_STORAGE_PERSIST_COUNT, 1);
+  return ExecuteOpOnMainOrWorkerThread(mOwner, RequestResolver::Type::Persist,
+                                       aRv);
+}
+
+already_AddRefed<Promise> StorageManager::Estimate(ErrorResult& aRv) {
+  MOZ_ASSERT(mOwner);
+
+  Telemetry::ScalarAdd(Telemetry::ScalarID::NAVIGATOR_STORAGE_ESTIMATE_COUNT,
+                       1);
+  return ExecuteOpOnMainOrWorkerThread(mOwner, RequestResolver::Type::Estimate,
+                                       aRv);
+}
+
+already_AddRefed<Promise> StorageManager::GetDirectory(ErrorResult& aRv) {
+  return RefPtr(GetFileSystemManager())->GetDirectory(aRv);
+}
+
+}  // namespace mozilla::dom
diff --git a/dom/quota/StorageManager.h b/dom/quota/StorageManager.h
new file mode 100644
index 0000000000..8622c1eb5d
--- /dev/null
+++ b/dom/quota/StorageManager.h
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_StorageManager_h
+#define mozilla_dom_StorageManager_h
+
+#include "js/TypeDecls.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "nsCOMPtr.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsISupports.h"
+#include "nsWrapperCache.h"
+
+class JSObject;
+class nsIGlobalObject;
+struct JSContext;
+
+namespace mozilla {
+class ErrorResult;
+
+namespace dom {
+
+class FileSystemManager;
+class Promise;
+struct StorageEstimate;
+
+class StorageManager final : public nsISupports, public nsWrapperCache {
+  nsCOMPtr<nsIGlobalObject> mOwner;
+
+ public:
+  explicit StorageManager(nsIGlobalObject* aGlobal);
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(StorageManager)
+
+  void Shutdown();
+
+  already_AddRefed<FileSystemManager> GetFileSystemManager();
+
+  // WebIDL Boilerplate
+  nsIGlobalObject* GetParentObject() const { return mOwner; }
+
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Interface
+  already_AddRefed<Promise> Persisted(ErrorResult& aRv);
+
+  already_AddRefed<Promise> Persist(ErrorResult& aRv);
+
+  already_AddRefed<Promise> Estimate(ErrorResult& aRv);
+
+  already_AddRefed<Promise> GetDirectory(ErrorResult& aRv);
+
+ private:
+  ~StorageManager();
+
+  RefPtr<FileSystemManager> mFileSystemManager;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_StorageManager_h
diff --git a/dom/quota/UsageInfo.h b/dom/quota/UsageInfo.h
new file mode 100644
index 0000000000..7f7bf5f85a
--- /dev/null
+++ b/dom/quota/UsageInfo.h
@@ -0,0 +1,103 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_quota_usageinfo_h__
+#define mozilla_dom_quota_usageinfo_h__
+
+#include <cstdint>
+#include <utility>
+#include "mozilla/CheckedInt.h"
+#include "mozilla/Maybe.h"
+
+namespace mozilla::dom::quota {
+
+enum struct UsageKind { Database, File };
+
+namespace detail {
+inline void AddCapped(Maybe<uint64_t>& aValue, const Maybe<uint64_t> aDelta) {
+  if (aDelta.isSome()) {
+    CheckedUint64 value = aValue.valueOr(0);
+
+    value += aDelta.value();
+
+    aValue = Some(value.isValid() ? value.value() : UINT64_MAX);
+  }
+}
+
+template <UsageKind Kind>
+struct Usage {
+  explicit Usage(Maybe<uint64_t> aValue = Nothing{}) : mValue(aValue) {}
+
+  Maybe<uint64_t> GetValue() const { return mValue; }
+
+  Usage& operator+=(const Usage aDelta) {
+    AddCapped(mValue, aDelta.mValue);
+
+    return *this;
+  }
+
+  Usage operator+(const Usage aDelta) const {
+    Usage res = *this;
+    res += aDelta;
+    return res;
+  }
+
+ private:
+  Maybe<uint64_t> mValue;
+};
+}  // namespace detail
+
+using DatabaseUsageType = detail::Usage<UsageKind::Database>;
+using FileUsageType = detail::Usage<UsageKind::File>;
+
+class UsageInfo final {
+ public:
+  UsageInfo() = default;
+
+  explicit UsageInfo(const DatabaseUsageType aUsage) : mDatabaseUsage(aUsage) {}
+
+  explicit UsageInfo(const FileUsageType aUsage) : mFileUsage(aUsage) {}
+
+  UsageInfo operator+(const UsageInfo& aUsageInfo) {
+    UsageInfo res = *this;
+    res += aUsageInfo;
+    return res;
+  }
+
+  UsageInfo& operator+=(const UsageInfo& aUsageInfo) {
+    mDatabaseUsage += aUsageInfo.mDatabaseUsage;
+    mFileUsage += aUsageInfo.mFileUsage;
+    return *this;
+  }
+
+  UsageInfo& operator+=(const DatabaseUsageType aUsage) {
+    mDatabaseUsage += aUsage;
+    return *this;
+  }
+
+  UsageInfo& operator+=(const FileUsageType aUsage) {
+    mFileUsage += aUsage;
+    return *this;
+  }
+
+  Maybe<uint64_t> DatabaseUsage() const { return mDatabaseUsage.GetValue(); }
+
+  Maybe<uint64_t> FileUsage() const { return mFileUsage.GetValue(); }
+
+  Maybe<uint64_t> TotalUsage() const {
+    Maybe<uint64_t> res = mDatabaseUsage.GetValue();
+    detail::AddCapped(res, FileUsage());
+    return res;
+  }
+
+ private:
+  DatabaseUsageType mDatabaseUsage;
+  FileUsageType mFileUsage;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // mozilla_dom_quota_usageinfo_h__
diff --git a/dom/quota/components.conf b/dom/quota/components.conf
new file mode 100644
index 0000000000..b55e861e0f
--- /dev/null
+++ b/dom/quota/components.conf
@@ -0,0 +1,23 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Classes = [
+    {
+        'cid': '{b6f2f870-b0bc-4a1a-9c40-02cc171adb5b}',
+        'contract_ids': ['@mozilla.org/network/protocol;1?name=indexeddb'],
+        'type': 'nsIndexedDBProtocolHandler',
+        'headers': ['/dom/quota/nsIndexedDBProtocolHandler.h'],
+        'protocol_config': {
+            'scheme': 'indexeddb',
+            'flags': [
+                'URI_STD',
+                'URI_DANGEROUS_TO_LOAD',
+                'URI_DOES_NOT_RETURN_DATA',
+                'URI_NON_PERSISTABLE',
+            ],
+        },
+    },
+]
diff --git a/dom/quota/moz.build b/dom/quota/moz.build
new file mode 100644
index 0000000000..b4416a4bed
--- /dev/null
+++ b/dom/quota/moz.build
@@ -0,0 +1,120 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+with Files("**"):
+    BUG_COMPONENT = ("Core", "Storage: Quota Manager")
+
+DIRS += ["test"]
+
+XPIDL_SOURCES += [
+    "nsIQuotaCallbacks.idl",
+    "nsIQuotaManagerService.idl",
+    "nsIQuotaRequests.idl",
+    "nsIQuotaResults.idl",
+]
+
+XPIDL_MODULE = "dom_quota"
+
+EXPORTS.mozilla.dom += [
+    "QMResult.h",
+    "StorageManager.h",
+]
+
+EXPORTS.mozilla.dom.quota += [
+    "ActorsParent.h",
+    "Assertions.h",
+    "AssertionsImpl.h",
+    "CachingDatabaseConnection.h",
+    "CheckedUnsafePtr.h",
+    "CipherStrategy.h",
+    "Client.h",
+    "ClientImpl.h",
+    "CommonMetadata.h",
+    "Config.h",
+    "DecryptingInputStream.h",
+    "DecryptingInputStream_impl.h",
+    "DirectoryLock.h",
+    "DummyCipherStrategy.h",
+    "EncryptedBlock.h",
+    "EncryptingOutputStream.h",
+    "EncryptingOutputStream_impl.h",
+    "FileStreams.h",
+    "FirstInitializationAttempts.h",
+    "FirstInitializationAttemptsImpl.h",
+    "ForwardDecls.h",
+    "InitializationTypes.h",
+    "IPCStreamCipherStrategy.h",
+    "NSSCipherStrategy.h",
+    "OriginScope.h",
+    "PersistenceType.h",
+    "QuotaCommon.h",
+    "QuotaManager.h",
+    "QuotaManagerImpl.h",
+    "QuotaManagerService.h",
+    "QuotaObject.h",
+    "RemoteQuotaObjectChild.h",
+    "RemoteQuotaObjectParent.h",
+    "RemoteQuotaObjectParentTracker.h",
+    "RemoveParen.h",
+    "ResultExtensions.h",
+    "ScopedLogExtraInfo.h",
+    "SerializationHelpers.h",
+    "StorageHelpers.h",
+    "UsageInfo.h",
+]
+
+XPCOM_MANIFESTS += [
+    "components.conf",
+]
+
+UNIFIED_SOURCES += [
+    "ActorsChild.cpp",
+    "ActorsParent.cpp",
+    "CachingDatabaseConnection.cpp",
+    "CanonicalQuotaObject.cpp",
+    "Client.cpp",
+    "ClientUsageArray.cpp",
+    "DecryptingInputStream.cpp",
+    "DirectoryLockImpl.cpp",
+    "EncryptingOutputStream.cpp",
+    "FileStreams.cpp",
+    "GroupInfo.cpp",
+    "GroupInfoPair.cpp",
+    "InitializationTypes.cpp",
+    "nsIndexedDBProtocolHandler.cpp",
+    "NSSCipherStrategy.cpp",
+    "OriginInfo.cpp",
+    "PersistenceType.cpp",
+    "QMResult.cpp",
+    "QuotaCommon.cpp",
+    "QuotaManagerService.cpp",
+    "QuotaObject.cpp",
+    "QuotaRequests.cpp",
+    "QuotaResults.cpp",
+    "RemoteQuotaObject.cpp",
+    "RemoteQuotaObjectChild.cpp",
+    "RemoteQuotaObjectParent.cpp",
+    "ScopedLogExtraInfo.cpp",
+    "StorageHelpers.cpp",
+    "StorageManager.cpp",
+]
+
+IPDL_SOURCES += [
+    "IPCQuotaObject.ipdlh",
+    "PQuota.ipdl",
+    "PQuotaRequest.ipdl",
+    "PQuotaUsageRequest.ipdl",
+    "PRemoteQuotaObject.ipdl",
+]
+
+include("/ipc/chromium/chromium-config.mozbuild")
+
+FINAL_LIBRARY = "xul"
+
+LOCAL_INCLUDES += [
+    "/caps",
+    "/dom/fs/include",
+]
diff --git a/dom/quota/nsIQuotaCallbacks.idl b/dom/quota/nsIQuotaCallbacks.idl
new file mode 100644
index 0000000000..7c53db20c0
--- /dev/null
+++ b/dom/quota/nsIQuotaCallbacks.idl
@@ -0,0 +1,22 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIQuotaRequest;
+interface nsIQuotaUsageRequest;
+
+[scriptable, function, uuid(c8a21a2a-17b9-4b63-ad95-e0fbcff5de18)]
+interface nsIQuotaUsageCallback : nsISupports
+{
+  void onUsageResult(in nsIQuotaUsageRequest aRequest);
+};
+
+[scriptable, function, uuid(a08a28e2-5a74-4c84-8070-ed45a07eb013)]
+interface nsIQuotaCallback : nsISupports
+{
+  void onComplete(in nsIQuotaRequest aRequest);
+};
diff --git a/dom/quota/nsIQuotaManagerService.idl b/dom/quota/nsIQuotaManagerService.idl
new file mode 100644
index 0000000000..9855283a5f
--- /dev/null
+++ b/dom/quota/nsIQuotaManagerService.idl
@@ -0,0 +1,296 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIPrincipal;
+interface nsIQuotaRequest;
+interface nsIQuotaCallback;
+interface nsIQuotaUsageCallback;
+interface nsIQuotaUsageRequest;
+
+[scriptable, builtinclass, uuid(1b3d0a38-8151-4cf9-89fa-4f92c2ef0e7e)]
+interface nsIQuotaManagerService : nsISupports
+{
+  /**
+   * Asynchronously retrieves storage name and returns it as a plain string.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  storageName();
+
+  /**
+   * Check if storage is initialized.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  storageInitialized();
+
+  /**
+   * Check if temporary storage is initialized.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  temporaryStorageInitialized();
+
+  /**
+   * Initializes storage directory. This can be used in tests to verify
+   * upgrade methods.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  init();
+
+  /**
+   * Initializes temporary storage. This can be used in tests to verify
+   * temporary storage initialization.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  initTemporaryStorage();
+
+  /**
+   * Initializes persistent origin directory for the given origin. This can be
+   * used in tests to verify origin initialization.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   *
+   * @param aPrincipal
+   *        A principal for the origin whose directory is to be initialized.
+   */
+  [must_use] nsIQuotaRequest
+  initializePersistentOrigin(in nsIPrincipal aPrincipal);
+
+  /**
+   * Initializes temporary origin directory for the given origin. This can be
+   * used in tests to verify origin initialization.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   *
+   * @param aPersistenceType
+   *        A string that tells what persistence type of origin will be
+   *        initialized (temporary or default).
+   *
+   * @param aPrincipal
+   *        A principal for the origin whose directory is to be initialized.
+   */
+  [must_use] nsIQuotaRequest
+  initializeTemporaryOrigin(in ACString aPersistenceType,
+                            in nsIPrincipal aPrincipal);
+
+  /**
+   * Gets full origin metadata cached in memory for the given persistence type
+   * and origin.
+   *
+   * NOTE: This operation may still be delayed by other operations on the QM
+   *       I/O thread that are peforming I/O.
+   *
+   * @param aPersistenceType
+   *        A string that tells what persistence type will be used for getting
+   *        the metadata (either "temporary" or "default").
+   * @param aPrincipal
+   *        A principal that tells which origin will be used for getting the
+   *        metadata.
+   */
+  [must_use] nsIQuotaRequest
+  getFullOriginMetadata(in ACString aPersistenceType,
+                        in nsIPrincipal aPrincipal);
+
+  /**
+   * Schedules an asynchronous callback that will inspect all origins and
+   * return the total amount of disk space being used by storages for each
+   * origin separately.
+   *
+   * @param aCallback
+   *        The callback that will be called when the usage is available.
+   * @param aGetAll
+   *        An optional boolean to indicate inspection of all origins,
+   *        including internal ones.
+   */
+  [must_use] nsIQuotaUsageRequest
+  getUsage(in nsIQuotaUsageCallback aCallback,
+           [optional] in boolean aGetAll);
+
+  /**
+   * Schedules an asynchronous callback that will return the total amount of
+   * disk space being used by storages for the given origin.
+   *
+   * @param aPrincipal
+   *        A principal for the origin whose usage is being queried.
+   * @param aCallback
+   *        The callback that will be called when the usage is available.
+   * @param aFromMemory
+   *        An optional flag to indicate whether the cached usage should be
+   *        obtained. The default value is false.  Note that this operation may
+   *        still be delayed by other operations on the QM I/O thread that are
+   *        peforming I/O.
+   * Note:  Origin usage here represents total usage of an origin. However,
+   *        cached usage here represents only non-persistent usage of an origin.
+   */
+  [must_use] nsIQuotaUsageRequest
+  getUsageForPrincipal(in nsIPrincipal aPrincipal,
+                       in nsIQuotaUsageCallback aCallback,
+                       [optional] in boolean aFromMemory);
+
+  /**
+   * Asynchronously lists all origins and returns them as plain strings.
+   */
+  [must_use] nsIQuotaRequest
+  listOrigins();
+
+  /**
+   * Removes all storages. The files may not be deleted immediately depending
+   * on prohibitive concurrent operations.
+   * Be careful, this removes *all* the data that has ever been stored!
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  clear();
+
+  /**
+   * Removes all storages stored for the given pattern. The files may not be
+   * deleted immediately depending on prohibitive concurrent operations.  In
+   * terms of locks, it will get an exclusive multi directory lock for given
+   * pattern.  For example, given pattern {"userContextId":1007} and set of 3
+   * origins ["http://www.mozilla.org^userContextId=1007",
+   * "http://www.example.org^userContextId=1007",
+   * "http://www.example.org^userContextId=1008"], the method will only lock 2
+   * origins ["http://www.mozilla.org^userContextId=1007",
+   * "http://www.example.org^userContextId=1007"].
+   *
+   * @param aPattern
+   *        A pattern for the origins whose storages are to be cleared.
+   *        Currently this is expected to be a JSON representation of the
+   *        OriginAttributesPatternDictionary defined in ChromeUtils.webidl.
+   */
+  [must_use] nsIQuotaRequest
+  clearStoragesForOriginAttributesPattern(in AString aPattern);
+
+  /**
+   * Removes all storages stored for the given principal. The files may not be
+   * deleted immediately depending on prohibitive concurrent operations.
+   *
+   * @param aPrincipal
+   *        A principal for the origin whose storages are to be cleared.
+   * @param aPersistenceType
+   *        An optional string that tells what persistence type of storages
+   *        will be cleared.  If omitted (or void), all persistence types will
+   *        be cleared for the principal.  If a single persistence type
+   *        ("persistent", "temporary", or "default") is provided, then only
+   *        that persistence directory will be considered.  Note that
+   *        "persistent" is different than being "persisted" via persist() and
+   *        is only for chrome principals.  See bug 1354500 for more info.
+   *        In general, null is the right thing to pass here.
+   * @param aClientType
+   *        An optional string that tells what client type of storages
+   *        will be cleared.  If omitted (or void), all client types will be
+   *        cleared for the principal.  If a single client type is provided
+   *        from Client.h, then only that client's storage will be cleared.
+   *        If you want to clear multiple client types (but not all), then you
+   *        must call this method multiple times.
+   * @param aClearAll
+   *        An optional boolean to indicate clearing all storages under the
+   *        given origin.
+   */
+  [must_use] nsIQuotaRequest
+  clearStoragesForPrincipal(in nsIPrincipal aPrincipal,
+                            [optional] in ACString aPersistenceType,
+                            [optional] in AString aClientType,
+                            [optional] in boolean aClearAll);
+
+  /**
+   * Resets quota and storage management. This can be used to force
+   * reinitialization of the temp storage, for example when the pref for
+   * overriding the temp storage limit has changed.
+   * Be carefull, this invalidates all live storages!
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   */
+  [must_use] nsIQuotaRequest
+  reset();
+
+  /**
+   * Resets all storages stored for the given principal.
+   *
+   * If the dom.quotaManager.testing preference is not true the call will be
+   * a no-op.
+   *
+   * @param aPrincipal
+   *        A principal for the origin whose storages are to be reset.
+   * @param aPersistenceType
+   *        An optional string that tells what persistence type of storages
+   *        will be reset.  If omitted (or void), all persistence types will
+   *        be cleared for the principal.  If a single persistence type
+   *        ("persistent", "temporary", or "default") is provided, then only
+   *        that persistence directory will be considered.  Note that
+   *        "persistent" is different than being "persisted" via persist() and
+   *        is only for chrome principals.  See bug 1354500 for more info.
+   *        In general, null is the right thing to pass here.
+   * @param aClientType
+   *        An optional string that tells what client type of storages
+   *        will be reset.  If omitted (or void), all client types will be
+   *        cleared for the principal.  If a single client type is provided
+   *        from Client.h, then only that client's storage will be cleared.
+   *        If you want to clear multiple client types (but not all), then you
+   *        must call this method multiple times.
+   */
+  [must_use] nsIQuotaRequest
+  resetStoragesForPrincipal(in nsIPrincipal aPrincipal,
+                            [optional] in ACString aPersistenceType,
+                            [optional] in AString aClientType);
+
+  /**
+   * Check if given origin is persisted.
+   *
+   * @param aPrincipal
+   *        A principal for the origin which we want to check.
+   */
+  [must_use] nsIQuotaRequest
+  persisted(in nsIPrincipal aPrincipal);
+
+  /**
+   * Persist given origin.
+   *
+   * @param aPrincipal
+   *        A principal for the origin which we want to persist.
+   */
+  [must_use] nsIQuotaRequest
+  persist(in nsIPrincipal aPrincipal);
+
+  /**
+   * Given an origin, asynchronously calculate its group quota usage and quota
+   * limit. An origin's group is the set of all origins that share the same
+   * eTLD+1. This method is intended to be used for our implementation of the
+   * StorageManager.estimate() method. When we fix bug 1305665 and stop tracking
+   * quota limits on a group basis, this method will switch to operating on
+   * origins. Callers should strongly consider whether they want to be using
+   * getUsageForPrincipal() instead.
+   *
+   * This mechanism uses cached quota values and does not perform any I/O on its
+   * own, but it may be delayed by QuotaManager operations that do need to
+   * perform I/O on the QuotaManager I/O thread.
+   *
+   * @param aPrincipal
+   *        A principal for the origin (group) which we want to estimate.
+   */
+  [must_use] nsIQuotaRequest
+  estimate(in nsIPrincipal aPrincipal);
+};
diff --git a/dom/quota/nsIQuotaRequests.idl b/dom/quota/nsIQuotaRequests.idl
new file mode 100644
index 0000000000..8b05717e83
--- /dev/null
+++ b/dom/quota/nsIQuotaRequests.idl
@@ -0,0 +1,49 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIPrincipal;
+interface nsIQuotaCallback;
+interface nsIQuotaUsageCallback;
+interface nsIVariant;
+
+[scriptable, uuid(9af54222-0407-48fd-a4ab-9457c986fc49)]
+interface nsIQuotaRequestBase : nsISupports
+{
+  readonly attribute nsIPrincipal principal;
+
+  [must_use] readonly attribute nsresult resultCode;
+
+  [must_use] readonly attribute ACString resultName;
+};
+
+[scriptable, uuid(166e28e6-cf6d-4927-a6d7-b51bca9d3469)]
+interface nsIQuotaUsageRequest : nsIQuotaRequestBase
+{
+  // The result can contain one of these types:
+  //   array of nsIQuotaUsageResult
+  //   nsIQuotaOriginUsageResult
+  [must_use] readonly attribute nsIVariant result;
+
+  attribute nsIQuotaUsageCallback callback;
+
+  [must_use] void
+  cancel();
+};
+
+[scriptable, uuid(22890e3e-ff25-4372-9684-d901060e2f6c)]
+interface nsIQuotaRequest : nsIQuotaRequestBase
+{
+  // The result can contain one of these types:
+  //   void
+  //   bool
+  //   nsIQuotaEstimateResult
+  //   array of strings
+  [must_use] readonly attribute nsIVariant result;
+
+  attribute nsIQuotaCallback callback;
+};
diff --git a/dom/quota/nsIQuotaResults.idl b/dom/quota/nsIQuotaResults.idl
new file mode 100644
index 0000000000..bf9ab322b8
--- /dev/null
+++ b/dom/quota/nsIQuotaResults.idl
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+[scriptable, function, uuid(4d8def75-014e-404d-bf30-e2f0Bfcf4d89)]
+interface nsIQuotaFullOriginMetadataResult : nsISupports
+{
+  readonly attribute ACString suffix;
+
+  readonly attribute ACString group;
+
+  readonly attribute ACString origin;
+
+  readonly attribute ACString persistenceType;
+
+  readonly attribute boolean persisted;
+
+  readonly attribute long long lastAccessTime;
+};
+
+[scriptable, function, uuid(d8c9328b-9aa8-4f5d-90e6-482de4a6d5b8)]
+interface nsIQuotaUsageResult : nsISupports
+{
+  readonly attribute ACString origin;
+
+  readonly attribute boolean persisted;
+
+  readonly attribute unsigned long long usage;
+
+  readonly attribute unsigned long long lastAccessed;
+};
+
+[scriptable, function, uuid(96df03d2-116a-493f-bb0b-118c212a6b32)]
+interface nsIQuotaOriginUsageResult : nsISupports
+{
+  readonly attribute unsigned long long usage;
+
+  readonly attribute unsigned long long fileUsage;
+};
+
+[scriptable, function, uuid(9827fc69-7ea9-48ef-b30d-2e2ae0451ec0)]
+interface nsIQuotaEstimateResult : nsISupports
+{
+  readonly attribute unsigned long long usage;
+
+  readonly attribute unsigned long long limit;
+};
diff --git a/dom/quota/nsIndexedDBProtocolHandler.cpp b/dom/quota/nsIndexedDBProtocolHandler.cpp
new file mode 100644
index 0000000000..10ca278098
--- /dev/null
+++ b/dom/quota/nsIndexedDBProtocolHandler.cpp
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim:set ts=2 sts=2 sw=2 et cin:
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIndexedDBProtocolHandler.h"
+
+#include <cstdint>
+#include "ErrorList.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/MacroForEach.h"
+#include "nsIWeakReference.h"
+#include "nsStandardURL.h"
+#include "nsStringFwd.h"
+#include "nscore.h"
+
+using namespace mozilla::net;
+
+nsIndexedDBProtocolHandler::nsIndexedDBProtocolHandler() = default;
+
+nsIndexedDBProtocolHandler::~nsIndexedDBProtocolHandler() = default;
+
+NS_IMPL_ISUPPORTS(nsIndexedDBProtocolHandler, nsIProtocolHandler,
+                  nsISupportsWeakReference)
+
+NS_IMETHODIMP nsIndexedDBProtocolHandler::GetScheme(nsACString& aScheme) {
+  aScheme.AssignLiteral("indexeddb");
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsIndexedDBProtocolHandler::NewChannel(nsIURI* aURI, nsILoadInfo* aLoadInfo,
+                                       nsIChannel** _retval) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+nsIndexedDBProtocolHandler::AllowPort(int32_t aPort, const char* aScheme,
+                                      bool* _retval) {
+  *_retval = false;
+  return NS_OK;
+}
diff --git a/dom/quota/nsIndexedDBProtocolHandler.h b/dom/quota/nsIndexedDBProtocolHandler.h
new file mode 100644
index 0000000000..00cc554cb4
--- /dev/null
+++ b/dom/quota/nsIndexedDBProtocolHandler.h
@@ -0,0 +1,26 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsIndexedDBProtocolHandler_h
+#define nsIndexedDBProtocolHandler_h
+
+#include "nsIProtocolHandler.h"
+#include "nsISupports.h"
+#include "nsWeakReference.h"
+
+class nsIndexedDBProtocolHandler final : public nsIProtocolHandler,
+                                         public nsSupportsWeakReference {
+ public:
+  nsIndexedDBProtocolHandler();
+
+ private:
+  ~nsIndexedDBProtocolHandler();
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIPROTOCOLHANDLER
+};
+
+#endif  // nsIndexedDBProtocolHandler_h
diff --git a/dom/quota/scripts/analyze_qm_failures.py b/dom/quota/scripts/analyze_qm_failures.py
new file mode 100755
index 0000000000..f4afd64ab4
--- /dev/null
+++ b/dom/quota/scripts/analyze_qm_failures.py
@@ -0,0 +1,137 @@
+#!/usr/bin/env python3
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import getopt
+import sys
+
+import fn_anchors
+import stackanalysis
+import utils
+
+"""
+The analysis is based on stack frames of the following form:
+
+[
+    {
+        "event_timeabs": 1617121013137,
+        "session_startabs": 1617120840000,
+        "build_id": "20210329095128",
+        "client_id": "0013a68f-9893-461a-93d4-2d7a2f85583f",
+        "session_id": "8cd37159-bd5c-481c-99ad-9eace9ea726a",
+        "seq": 1,
+        "context": "Initialization::TemporaryStorage",
+        "source_file": "dom/localstorage/ActorsParent.cpp",
+        "source_line": "1018",
+        "severity": "ERROR",
+        "result": "NS_ERROR_FILE_NOT_FOUND"
+    },
+...
+]
+
+The location of the input file is expected to be found in the
+last item of the list inside qmexecutions.json.
+"""
+
+
+def usage():
+    print("analyze_qm_faiures.py -w <workdir=.>")
+    print("")
+    print("Analyzes the results from fetch_qm_failures.py's JSON file.")
+    print(
+        "Writes out several JSON results as files and a bugzilla markup table on stdout."
+    )
+    print("-w <workdir>:       Working directory, default is '.'")
+    sys.exit(2)
+
+
+days = 1
+workdir = "."
+
+try:
+    opts, args = getopt.getopt(sys.argv[1:], "w:", ["workdir="])
+    for opt, arg in opts:
+        if opt == "-w":
+            workdir = arg
+except getopt.GetoptError:
+    usage()
+
+run = utils.getLastRunFromExecutionFile(workdir)
+if "numrows" not in run:
+    print("No previous execution from fetch_qm_failures.py found.")
+    usage()
+if run["numrows"] == 0:
+    print("The last execution yielded no result.")
+
+infile = run["rawfile"]
+
+
+def getFname(prefix):
+    return "{}/{}_until_{}.json".format(workdir, prefix, run["lasteventtime"])
+
+
+# read rows from JSON
+rows = utils.readJSONFile(getFname("qmrows"))
+print("Found {} rows of data.".format(len(rows)))
+rows = stackanalysis.sanitize(rows)
+
+# enrich rows with hg locations
+buildids = stackanalysis.extractBuildIDs(rows)
+utils.fetchBuildRevisions(buildids)
+stackanalysis.constructHGLinks(buildids, rows)
+
+# transform rows to unique stacks
+raw_stacks = stackanalysis.collectRawStacks(rows)
+all_stacks = stackanalysis.mergeEqualStacks(raw_stacks)
+
+# enrich with function anchors
+for stack in all_stacks:
+    for frame in stack["frames"]:
+        frame["anchor"] = "{}:{}".format(
+            frame["source_file"], fn_anchors.getFunctionName(frame["location"])
+        )
+
+# separate stacks for relevance
+error_stacks = []
+warn_stacks = []
+info_stacks = []
+abort_stacks = []
+stackanalysis.filterStacksForPropagation(
+    all_stacks, error_stacks, warn_stacks, info_stacks, abort_stacks
+)
+run["errorfile"] = getFname("qmerrors")
+utils.writeJSONFile(run["errorfile"], error_stacks)
+run["warnfile"] = getFname("qmwarnings")
+utils.writeJSONFile(run["warnfile"], warn_stacks)
+run["infofile"] = getFname("qminfo")
+utils.writeJSONFile(run["infofile"], info_stacks)
+run["abortfile"] = getFname("qmabort")
+utils.writeJSONFile(run["abortfile"], abort_stacks)
+utils.updateLastRunToExecutionFile(workdir, run)
+
+
+# print results to stdout
+print("Found {} error stacks.".format(len(error_stacks)))
+print("Found {} warning stacks.".format(len(warn_stacks)))
+print("Found {} info stacks.".format(len(info_stacks)))
+print("Found {} aborted stacks.".format(len(abort_stacks)))
+print("")
+print("Error stacks:")
+print(stackanalysis.printStacks(error_stacks))
+print("")
+print("Error stacks grouped by anchors:")
+anchors = stackanalysis.groupStacksForAnchors(error_stacks)
+anchornames = list(anchors.keys())
+for a in anchornames:
+    print(stackanalysis.printStacks(anchors[a]["stacks"]))
+    print("")
+print("")
+print("Warning stacks:")
+print(stackanalysis.printStacks(warn_stacks))
+print("")
+print("Info stacks:")
+print(stackanalysis.printStacks(info_stacks))
+print("")
+print("Aborted stacks:")
+print(stackanalysis.printStacks(abort_stacks))
diff --git a/dom/quota/scripts/fetch_fn_names.sh b/dom/quota/scripts/fetch_fn_names.sh
new file mode 100755
index 0000000000..6d3a3c4d23
--- /dev/null
+++ b/dom/quota/scripts/fetch_fn_names.sh
@@ -0,0 +1,17 @@
+#!/bin/bash
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# This script assumes to have rust-code-analysis-cli in the path.
+HG_URL=$1
+TEMPDIR=/tmp/fetch_fn_names_$BASHPID
+TEMPSRC=$TEMPDIR/src
+mkdir $TEMPDIR
+echo "" > $TEMPDIR/empty.json
+HG_URL=`echo $HG_URL | sed 's/annotate/raw-file/g'`
+wget -q -O "$TEMPSRC" $HG_URL
+rust-code-analysis-cli -m -O json -o "$TEMPDIR" -p "$TEMPSRC"
+CONTENT=`cat $TEMPDIR/*.json`
+rm -rf $TEMPDIR
+echo $CONTENT
diff --git a/dom/quota/scripts/fetch_qm_failures.py b/dom/quota/scripts/fetch_qm_failures.py
new file mode 100755
index 0000000000..546b213582
--- /dev/null
+++ b/dom/quota/scripts/fetch_qm_failures.py
@@ -0,0 +1,142 @@
+#!/usr/bin/env python3
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import getopt
+import sys
+
+import telemetry
+import utils
+
+"""
+The analysis is based on the following query:
+https://sql.telemetry.mozilla.org/queries/78691/source?p_day=28&p_month=03&p_year=2021
+
+SELECT UNIX_MILLIS(timestamp) AS submit_timeabs,
+       session_start_time,
+       submission_date,
+       build_id,
+       client_id,
+       session_id,
+       event_timestamp,
+       CAST(mozfun.map.get_key(event_map_values, "seq") AS INT64) AS seq,
+       mozfun.map.get_key(event_map_values, "context") AS context,
+       mozfun.map.get_key(event_map_values, "source_file") AS source_file,
+       mozfun.map.get_key(event_map_values, "source_line") AS source_line,
+       mozfun.map.get_key(event_map_values, "severity") AS severity,
+       mozfun.map.get_key(event_map_values, "result") AS result,
+FROM telemetry.events
+WHERE submission_date >= CAST('{{ year }}-{{ month }}-{{ day }}' AS DATE)
+  AND event_category='dom.quota.try'
+  AND build_id >= '{{ build }}'
+  AND UNIX_MILLIS(timestamp) > {{ last }}
+ORDER BY submit_timeabs
+LIMIT 600000
+
+We fetch events in chronological order, as we want to keep track of where we already
+arrived with our analysis. To accomplish this we write our runs into qmexecutions.json.
+
+[
+    {
+        "workdir": ".",
+        "daysback": 1,
+        "numrows": 17377,
+        "lasteventtime": 1617303855145,
+        "rawfile": "./qmrows_until_1617303855145.json"
+    }
+]
+
+lasteventtime is the highest value of event_timeabs we found in our data.
+
+analyze_qm_failures instead needs the rows to be ordered by
+client_id, session_id, thread_id, submit_timeabs, seq
+Thus we sort the rows accordingly before writing them.
+"""
+
+
+def usage():
+    print(
+        "fetch_qm_faiures.py -k <apikey> -b <minimum build=20210329000000>"
+        "-d <days back=1> -l <last event time> -w <workdir=.>"
+    )
+    print("")
+    print("Invokes the query 78691 and stores the result in a JSON file.")
+    print("-k <apikey>:          Your personal telemetry API key (not the query key!).")
+    print("-d <daysback>:        Number of days to go back. Default is 1.")
+    print("-b <minimum build>:   The lowest build id we will fetch data for.")
+    print("-l <last event time>: Fetch only events after this. Default is 0.")
+    print("-w <workdir>:         Working directory, default is '.'")
+    sys.exit(2)
+
+
+days = 1
+lasteventtime = 0
+key = "undefined"
+workdir = "."
+minbuild = "20210329000000"
+
+try:
+    opts, args = getopt.getopt(
+        sys.argv[1:],
+        "k:b:d:l:w:",
+        ["key=", "build=", "days=", "lasteventtime=", "workdir="],
+    )
+    for opt, arg in opts:
+        if opt == "-k":
+            key = arg
+        elif opt == "-d":
+            days = int(arg)
+        elif opt == "-l":
+            lasteventtime = int(arg)
+        elif opt == "-b":
+            minbuild = arg
+        elif opt == "-w":
+            workdir = arg
+except getopt.GetoptError:
+    usage()
+
+if key == "undefined":
+    usage()
+
+start = utils.dateback(days)
+year = start.year
+month = start.month
+day = start.day
+
+run = {}
+lastrun = utils.getLastRunFromExecutionFile(workdir)
+if "lasteventtime" in lastrun:
+    lasteventtime = lastrun["lasteventtime"]
+run["workdir"] = workdir
+run["daysback"] = days
+run["minbuild"] = minbuild
+
+p_params = "p_year={:04d}&p_month={:02d}&p_day={:02d}&p_build={}" "&p_last={}".format(
+    year, month, day, minbuild, lasteventtime
+)
+print(p_params)
+result = telemetry.query(key, 78691, p_params)
+rows = result["query_result"]["data"]["rows"]
+run["numrows"] = len(rows)
+if run["numrows"] > 0:
+    lasteventtime = telemetry.getLastEventTimeAbs(rows)
+    run["lasteventtime"] = lasteventtime
+    rows.sort(
+        key=lambda row: "{}.{}.{}.{}.{:06d}".format(
+            row["client_id"],
+            row["session_id"],
+            row["seq"] >> 32,  # thread_id
+            row["submit_timeabs"],
+            row["seq"] & 0x00000000FFFFFFFF,  # seq,
+        ),
+        reverse=False,
+    )
+    outfile = "{}/qmrows_until_{}.json".format(workdir, lasteventtime)
+    utils.writeJSONFile(outfile, rows)
+    run["rawfile"] = outfile
+else:
+    print("No results found, maybe next time.")
+    run["lasteventtime"] = lasteventtime
+
+utils.addNewRunToExecutionFile(workdir, run)
diff --git a/dom/quota/scripts/fn_anchors.py b/dom/quota/scripts/fn_anchors.py
new file mode 100644
index 0000000000..eeaf43764c
--- /dev/null
+++ b/dom/quota/scripts/fn_anchors.py
@@ -0,0 +1,68 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import json
+import subprocess
+
+cached_functions = {}
+
+
+def getMetricsJson(src_url):
+    if src_url.startswith("http"):
+        print("Fetching source for function extraction: {}".format(src_url))
+        metrics = subprocess.check_output(["./fetch_fn_names.sh", src_url])
+    else:
+        print("Skip fetching source: {}".format(src_url))
+        metrics = ""
+
+    try:
+        return json.loads(metrics)
+    except ValueError:
+        return {"kind": "empty", "name": "anonymous", "spaces": []}
+
+
+def getSpaceFunctionsRecursive(metrics_space):
+    functions = []
+    if (
+        metrics_space["kind"] == "function"
+        and metrics_space["name"]
+        and metrics_space["name"] != "<anonymous>"
+    ):
+        functions.append(
+            {
+                "name": metrics_space["name"],
+                "start_line": int(metrics_space["start_line"]),
+                "end_line": int(metrics_space["end_line"]),
+            }
+        )
+    for space in metrics_space["spaces"]:
+        functions += getSpaceFunctionsRecursive(space)
+    return functions
+
+
+def getSourceFunctions(src_url):
+    if src_url not in cached_functions:
+        metrics_space = getMetricsJson(src_url)
+        cached_functions[src_url] = getSpaceFunctionsRecursive(metrics_space)
+
+    return cached_functions[src_url]
+
+
+def getFunctionName(location):
+    location.replace("annotate", "raw-file")
+    pieces = location.split("#l")
+    src_url = pieces[0]
+    line = int(pieces[1])
+    closest_name = "<Unknown {}>".format(line)
+    closest_start = 0
+    functions = getSourceFunctions(src_url)
+    for fn in functions:
+        if (
+            fn["start_line"] > closest_start
+            and line >= fn["start_line"]
+            and line <= fn["end_line"]
+        ):
+            closest_start = fn["start_line"]
+            closest_name = fn["name"]
+    return closest_name
diff --git a/dom/quota/scripts/stackanalysis.py b/dom/quota/scripts/stackanalysis.py
new file mode 100644
index 0000000000..f0363c5e1f
--- /dev/null
+++ b/dom/quota/scripts/stackanalysis.py
@@ -0,0 +1,396 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+# There seem to be sometimes identical events recorded twice by telemetry
+def sanitize(rows):
+    newrows = []
+    pcid = "unset"
+    psid = "unset"
+    pseq = "unset"
+    for row in rows:
+        cid = row["client_id"]
+        sid = row["session_id"]
+        seq = row["seq"]
+        if cid != pcid or sid != psid or seq != pseq:
+            newrows.append(row)
+        pcid = cid
+        psid = sid
+        pseq = seq
+
+    return newrows
+
+
+# Given a set of rows, find all distinct build ids
+def extractBuildIDs(rows):
+    buildids = {}
+    for row in rows:
+        id = row["build_id"]
+        if id in buildids:
+            buildids[id] = buildids[id] + 1
+        else:
+            buildids[id] = 1
+    return buildids
+
+
+# Given a set of build ids and rows, enrich each row by an hg link.
+# Relys on the result of utils.fetchBuildRevisions in buildids.
+def constructHGLinks(buildids, rows):
+    for row in rows:
+        id = row["build_id"]
+        if id in buildids:
+            row["location"] = (
+                buildids[id] + "/" + row["source_file"] + "#l" + row["source_line"]
+            )
+        else:
+            row["location"] = id + "/" + row["source_file"] + "#l" + row["source_line"]
+
+
+topmost_stackframes = set()
+delta_frames = {}
+
+
+def isTopmostFrame(frame):
+    f = (frame["location"], frame["result"])
+    return f in topmost_stackframes
+
+
+def addTopmostFrame(frame):
+    f = (frame["location"], frame["result"])
+    if not isTopmostFrame(frame):
+        # print("Found new topmost frame {}.".format(frame))
+        topmost_stackframes.add(f)
+        frame["topmost"] = True
+
+
+def addFrameDelta(frame1, frame2):
+    if frame1["client_id"] != frame2["client_id"]:
+        return
+    if frame1["session_id"] != frame2["session_id"]:
+        return
+
+    fkey = "{}:{}-{}:{}".format(
+        frame2["location"], frame2["result"], frame1["location"], frame1["result"]
+    )
+    if fkey not in delta_frames:
+        fdelta = {"delta_sum": 0, "delta_cnt": 0}
+        fdelta["prev_row"] = frame1
+        fdelta["candidate"] = frame2
+        delta_frames[fkey] = fdelta
+
+    fdelta = delta_frames[fkey]
+    etv1 = frame1["event_timestamp"]
+    etv2 = frame2["event_timestamp"]
+    if isinstance(etv1, int) and isinstance(etv2, int) and etv2 > etv1:
+        delta = etv2 - etv1
+        fdelta["delta_sum"] = fdelta["delta_sum"] + delta
+        fdelta["delta_cnt"] = fdelta["delta_cnt"] + 1
+
+
+# There can be outliers in terms of time distance between two stack frames
+# that belong to the same propagation stack. In order to not increase the
+# risk that one outlier breaks thousands of stacks, we check for the average
+# time distance.
+def checkAverageFrameTimeDeltas(rows, max_delta):
+    # print("checkAverageFrameTimeDeltas")
+    prev_row = None
+    for row in rows:
+        if "topmost" in row or not row["session_complete"]:
+            prev_row = None
+            continue
+
+        if prev_row:
+            addFrameDelta(prev_row, row)
+        prev_row = row
+
+    for fd in delta_frames:
+        sum = delta_frames[fd]["delta_sum"]
+        cnt = delta_frames[fd]["delta_cnt"]
+        if cnt > 0 and (sum / cnt) > max_delta:
+            # print(delta_frames[fd])
+            addTopmostFrame(delta_frames[fd]["candidate"])
+
+
+# A topmost frame is considered to initiate a new raw stack. We collect all
+# candidates before we actually apply them. This implies, that we should run
+# this function on a "large enough" sample of rows to be more accurate.
+# As a side effect, we mark all rows that are part of a "complete" session
+# (a session, that started within our data scope).
+def collectTopmostFrames(rows):
+    prev_cid = "unset"
+    prev_sid = "unset"
+    prev_tid = "unset"
+    prev_ctx = "unset"
+    prev_sev = "ERROR"
+    session_complete = False
+    after_severity_downgrade = False
+    for row in rows:
+        cid = row["client_id"]
+        sid = row["session_id"]
+        tid = row["seq"] >> 32  # thread_id
+        ctx = row["context"]
+        seq = row["seq"] & 0x00000000FFFFFFFF  # seq
+        sev = row["severity"]
+
+        # If we have a new session, ensure it is complete from start,
+        # otherwise we will ignore it entirely.
+        if cid != prev_cid or sid != prev_sid or tid != prev_tid:
+            if seq == 1:
+                session_complete = True
+            else:
+                session_complete = False
+        row["session_complete"] = session_complete
+        if session_complete:
+            # If we change client, session, thread or context, we can be sure to have
+            # a new topmost frame.
+            if (
+                seq == 1
+                or cid != prev_cid
+                or sid != prev_sid
+                or tid != prev_tid
+                or ctx != prev_ctx
+            ):
+                addTopmostFrame(row)
+                after_severity_downgrade = False
+            # We do not expect a non-error to be ever upgraded to an error
+            elif sev == "ERROR" and prev_sev != "ERROR":
+                addTopmostFrame(row)
+                after_severity_downgrade = False
+            # If we just had a severity downgrade, we assume that we wanted
+            # to break the error propagation after this point and split, too
+            elif after_severity_downgrade:
+                addTopmostFrame(row)
+                after_severity_downgrade = False
+            elif prev_sev == "ERROR" and sev != "ERROR":
+                after_severity_downgrade = True
+
+        prev_cid = cid
+        prev_sid = sid
+        prev_tid = tid
+        prev_ctx = ctx
+        prev_sev = sev
+
+    # Should be ms. We've seen quite some runtime between stackframes in the
+    # wild. We might want to consider to make this configurable. In general
+    # we prefer local context over letting slip through some topmost frame
+    # unrecognized, assuming that fixing the issues one by one they will
+    # uncover them succesively. This is achieved by a rather high delta value.
+    max_avg_delta = 200
+    checkAverageFrameTimeDeltas(rows, max_avg_delta)
+
+
+def getFrameKey(frame):
+    return "{}.{}|".format(frame["location"], frame["result"])
+
+
+def getStackKey(stack):
+    stack_key = ""
+    for frame in stack["frames"]:
+        stack_key += getFrameKey(frame)
+    return hash(stack_key)
+
+
+# A "raw stack" is a list of frames, that:
+# - share the same build_id (implicitely through location)
+# - share the same client_id
+# - share the same session_id
+# - has a growing sequence number
+# - stops at the first downgrade of severity from ERROR to else
+# - XXX: contains each location at most once (no recursion)
+# - appears to be in a reasonable short timeframe
+# Calculates also a hash key to identify identical stacks
+def collectRawStacks(rows):
+    collectTopmostFrames(rows)
+    raw_stacks = []
+    stack = {
+        "stack_id": "unset",
+        "client_id": "unset",
+        "session_id": "unset",
+        "submit_timeabs": "unset",
+        "frames": [{"location": "unset"}],
+    }
+    stack_id = 1
+    first = True
+    for row in rows:
+        if isTopmostFrame(row):
+            if not first:
+                stack["stack_key"] = getStackKey(stack)
+                raw_stacks.append(stack)
+            stack_id += 1
+            stack = {
+                "stack_id": stack_id,
+                "client_id": row["client_id"],
+                "session_id": row["session_id"],
+                "submit_timeabs": row["submit_timeabs"],
+                "context": row["context"],
+                "frames": [],
+            }
+
+        stack["frames"].append(
+            {
+                "location": row["location"],
+                "source_file": row["source_file"],
+                "source_line": row["source_line"],
+                "seq": row["seq"],
+                "severity": row["severity"],
+                "result": row["result"],
+            }
+        )
+        first = False
+
+    return raw_stacks
+
+
+# Merge all stacks that have the same hash key and count occurences.
+# Relys on the ordering per client_id/session_id for correct counting.
+def mergeEqualStacks(raw_stacks):
+    merged_stacks = {}
+    last_client_id = "none"
+    last_session_id = "none"
+    for stack in raw_stacks:
+        stack_key = stack["stack_key"]
+        merged_stack = stack
+        if stack_key in merged_stacks:
+            merged_stack = merged_stacks[stack_key]
+            if stack["client_id"] != last_client_id:
+                last_client_id = stack["client_id"]
+                merged_stack["client_count"] += 1
+            if stack["session_id"] != last_session_id:
+                last_session_id = stack["session_id"]
+                merged_stack["session_count"] += 1
+            merged_stack["hit_count"] += 1
+        else:
+            merged_stack["client_count"] = 1
+            last_client_id = merged_stack["client_id"]
+            merged_stack["session_count"] = 1
+            last_session_id = merged_stack["session_id"]
+            merged_stack["hit_count"] = 1
+            merged_stacks[stack_key] = merged_stack
+
+    merged_list = list(merged_stacks.values())
+    merged_list.sort(key=lambda x: x.get("hit_count"), reverse=True)
+    return merged_list
+
+
+# Split the list of stacks into:
+# - aborted (has at least one frame with NS_ERROR_ABORT)
+# - info/warning (has at least one frame with that severity)
+# - error (has only error frames)
+def filterStacksForPropagation(
+    all_stacks, error_stacks, warn_stacks, info_stacks, abort_stacks
+):
+    for stack in all_stacks:
+        warn = list(filter(lambda x: x["severity"] == "WARNING", stack["frames"]))
+        info = list(filter(lambda x: x["severity"] == "INFO", stack["frames"]))
+        abort = list(filter(lambda x: x["result"] == "NS_ERROR_ABORT", stack["frames"]))
+        if len(abort) > 0:
+            abort_stacks.append(stack)
+        elif len(info) > 0:
+            info_stacks.append(stack)
+        elif len(warn) > 0:
+            warn_stacks.append(stack)
+        else:
+            error_stacks.append(stack)
+
+
+# Bugzilla comment markup
+def printStacks(stacks):
+    row_format = "{} | {} | {} | {} | {}\n"
+    out = ""
+    out += row_format.format("Clients", "Sessions", "Hits", "Anchor (Context)", "Stack")
+    out += row_format.format("-------", "--------", "----", "----------------", "-----")
+    for stack in stacks:
+        framestr = ""
+        first = True
+        for frame in stack["frames"]:
+            if not first:
+                framestr += " <- "
+            framestr += "[{}#{}:{}]({})".format(
+                frame["source_file"],
+                frame["source_line"],
+                frame["result"],
+                frame["location"],
+            )
+            first = False
+        out += row_format.format(
+            stack["client_count"],
+            stack["session_count"],
+            stack["hit_count"],
+            "{} ({})".format(stack["frames"][0]["anchor"], stack["context"]),
+            framestr,
+        )
+
+    return out
+
+
+def groupStacksForAnchors(stacks):
+    anchors = {}
+    for stack in stacks:
+        anchor_name = stack["frames"][0]["anchor"]
+        if anchor_name in anchors:
+            anchors[anchor_name]["stacks"].append(stack)
+        else:
+            anchor = {"anchor": anchor_name, "stacks": [stack]}
+            anchors[anchor_name] = anchor
+    return anchors
+
+
+"""
+def getSummaryForAnchor(anchor):
+    return "[QM_TRY] Errors in function {}".format(anchor)
+
+
+def searchBugForAnchor(bugzilla_key, anchor):
+    summary = getSummaryForAnchor(anchor)
+    bug_url = "https://bugzilla.mozilla.org/rest/bug?" \
+              "summary={}&api_key={}".format(summary, bugzilla_key)
+    return requests.get(url=bug_url).json()["bugs"]
+
+
+def createBugForAnchor(bugzilla_key, anchor):
+    summary = getSummaryForAnchor(anchor)
+    bug_url = "https://bugzilla.mozilla.org/rest/bug?" \
+              "Bugzilla_api_key={}".format(bugzilla_key)
+    body = {
+        "product" : "Core",
+        "component" : "Storage: Quota Manager",
+        "version" : "unspecified",
+        "summary" : summary,
+        "description" : "This bug collects errors reported by QM_TRY"
+                        "macros for function {}.".format(anchor),
+    }
+    resp = requests.post(url=bug_url, json=body)
+    if resp.status_code != 200:
+        print(resp)
+        return 0
+    id = resp.json()["id"]
+    print("Added new bug {}:".format(id))
+    return id
+
+
+def ensureBugForAnchor(bugzilla_key, anchor):
+    buglist = searchBugForAnchor(bugzilla_key, anchor)
+    if (len(buglist) > 0):
+        id = buglist[0]["id"]
+        print("Found existing bug {}:".format(id))
+        return id
+    return createBugForAnchor(bugzilla_key, anchor)
+
+
+def addCommentForAnchor(bugzilla_key, anchor, stacks):
+    id = ensureBugForAnchor(bugzilla_key, anchor)
+    if (id <= 0):
+        print("Unable to create a bug for {}.".format(anchor))
+        return
+    comment = printStacks(stacks)
+    print("")
+    print("Add comment to bug {}:".format(id))
+    print(comment)
+
+
+def addCommentsForStacks(bugzilla_key, stacks):
+    anchors = groupStacksForAnchors(stacks)
+    for anchor in anchors:
+        addCommentForAnchor(bugzilla_key, anchors[anchor]["anchor"], anchors[anchor]["stacks"])
+"""
diff --git a/dom/quota/scripts/telemetry.py b/dom/quota/scripts/telemetry.py
new file mode 100644
index 0000000000..a62abd62b1
--- /dev/null
+++ b/dom/quota/scripts/telemetry.py
@@ -0,0 +1,54 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import time
+
+import requests
+
+
+def query(key, query, p_params):
+    headers = {"Authorization": "Key {}".format(key)}
+    start_url = "https://sql.telemetry.mozilla.org/api/" "queries/{}/refresh?{}".format(
+        query, p_params
+    )
+    print(start_url)
+    resp = requests.post(url=start_url, headers=headers)
+    job = resp.json()["job"]
+    jid = job["id"]
+    print("Started job {}".format(jid))
+
+    poll_url = "https://sql.telemetry.mozilla.org/api/" "jobs/{}".format(jid)
+    print(poll_url)
+    poll = True
+    status = 0
+    qresultid = 0
+    while poll:
+        print(".", end="", flush=True)
+        resp = requests.get(url=poll_url, headers=headers)
+        status = resp.json()["job"]["status"]
+        if status > 2:
+            # print(resp.json())
+            poll = False
+            qresultid = resp.json()["job"]["query_result_id"]
+        else:
+            time.sleep(0.2)
+    print(".")
+    print("Finished with status {}".format(status))
+
+    if status == 3:
+        fetch_url = (
+            "https://sql.telemetry.mozilla.org/api/"
+            "queries/78691/results/{}.json".format(qresultid)
+        )
+        print(fetch_url)
+        resp = requests.get(url=fetch_url, headers=headers)
+        return resp.json()
+
+    return {"query_result": {"data": {"rows": {}}}}
+
+
+def getLastEventTimeAbs(rows):
+    if len(rows) == 0:
+        return 0
+    return rows[len(rows) - 1]["submit_timeabs"]
diff --git a/dom/quota/scripts/utils.py b/dom/quota/scripts/utils.py
new file mode 100644
index 0000000000..d5322728a5
--- /dev/null
+++ b/dom/quota/scripts/utils.py
@@ -0,0 +1,89 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import datetime
+import json
+
+import requests
+
+
+def readJSONFile(FileName):
+    f = open(FileName, "r")
+    p = json.load(f)
+    f.close()
+    return p
+
+
+def writeJSONFile(FileName, Content):
+    with open(FileName, "w") as outfile:
+        json.dump(Content, outfile, indent=4)
+
+
+def dateback(days):
+    today = datetime.date.today()
+    delta = datetime.timedelta(days)
+    return today - delta
+
+
+def lastweek():
+    today = datetime.date.today()
+    delta = datetime.timedelta(days=7)
+    return today - delta
+
+
+# Given a set of build ids, fetch the repository base URL for each id.
+def fetchBuildRevisions(buildids):
+    buildhub_url = "https://buildhub.moz.tools/api/search"
+    delids = {}
+    for bid in buildids:
+        print("Fetching revision for build {}.".format(bid))
+        body = {"size": 1, "query": {"term": {"build.id": bid}}}
+        resp = requests.post(url=buildhub_url, json=body)
+        hits = resp.json()["hits"]["hits"]
+        if len(hits) > 0:
+            buildids[bid] = (
+                hits[0]["_source"]["source"]["repository"]
+                + "/annotate/"
+                + hits[0]["_source"]["source"]["revision"]
+            )
+        else:
+            print("No revision for build.id {}".format(bid))
+            delids[bid] = "x"
+    for bid in delids:
+        buildids.pop(bid)
+
+
+def readExecutionFile(workdir):
+    exefile = "{}/qmexecutions.json".format(workdir)
+    try:
+        return readJSONFile(exefile)
+    except OSError:
+        return []
+
+
+def writeExecutionFile(workdir, executions):
+    exefile = "{}/qmexecutions.json".format(workdir)
+    try:
+        writeJSONFile(exefile, executions)
+    except OSError:
+        print("Error writing execution record.")
+
+
+def getLastRunFromExecutionFile(workdir):
+    executions = readExecutionFile(workdir)
+    if len(executions) > 0:
+        return executions[len(executions) - 1]
+    return {}
+
+
+def updateLastRunToExecutionFile(workdir, run):
+    executions = readExecutionFile(workdir)
+    executions[len(executions) - 1] = run
+    writeExecutionFile(workdir, executions)
+
+
+def addNewRunToExecutionFile(workdir, run):
+    executions = readExecutionFile(workdir)
+    executions.append(run)
+    writeExecutionFile(workdir, executions)
diff --git a/dom/quota/test/browser/browser.ini b/dom/quota/test/browser/browser.ini
new file mode 100644
index 0000000000..d0c79f90a9
--- /dev/null
+++ b/dom/quota/test/browser/browser.ini
@@ -0,0 +1,13 @@
+[DEFAULT]
+skip-if = (buildapp != "browser")
+support-files =
+  head.js
+  helpers.js
+  empty.html
+  permissionsPrompt.html
+
+[browser_permissionsCrossOrigin.js]
+[browser_permissionsPromptAllow.js]
+[browser_permissionsPromptDeny.js]
+[browser_permissionsPromptUnknown.js]
+[browser_simpledb.js]
diff --git a/dom/quota/test/browser/browser_permissionsCrossOrigin.js b/dom/quota/test/browser/browser_permissionsCrossOrigin.js
new file mode 100644
index 0000000000..6dcf32ff67
--- /dev/null
+++ b/dom/quota/test/browser/browser_permissionsCrossOrigin.js
@@ -0,0 +1,56 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const emptyURL =
+  "https://example.com/browser/dom/quota/test/browser/empty.html";
+
+addTest(async function testNoPermissionPrompt() {
+  registerPopupEventHandler("popupshowing", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+
+  info("Creating tab");
+
+  await BrowserTestUtils.withNewTab(emptyURL, async function(browser) {
+    await new Promise(r => {
+      SpecialPowers.pushPrefEnv(
+        {
+          set: [
+            ["permissions.delegation.enabled", true],
+            ["dom.security.featurePolicy.header.enabled", true],
+            ["dom.security.featurePolicy.webidl.enabled", true],
+          ],
+        },
+        r
+      );
+    });
+
+    await SpecialPowers.spawn(browser, [], async function(host0) {
+      let frame = content.document.createElement("iframe");
+      // Cross origin src
+      frame.src = "https://example.org/browser/dom/quota/test/empty.html";
+      content.document.body.appendChild(frame);
+      await ContentTaskUtils.waitForEvent(frame, "load");
+
+      await content.SpecialPowers.spawn(frame, [], async function() {
+        // Request a permission.
+        const persistAllowed = await this.content.navigator.storage.persist();
+        Assert.ok(
+          !persistAllowed,
+          "navigator.storage.persist() has been denied"
+        );
+      });
+      content.document.body.removeChild(frame);
+    });
+  });
+
+  unregisterAllPopupEventHandlers();
+});
diff --git a/dom/quota/test/browser/browser_permissionsPromptAllow.js b/dom/quota/test/browser/browser_permissionsPromptAllow.js
new file mode 100644
index 0000000000..4ddcfada96
--- /dev/null
+++ b/dom/quota/test/browser/browser_permissionsPromptAllow.js
@@ -0,0 +1,66 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const testPageURL =
+  "https://example.com/browser/dom/quota/test/browser/permissionsPrompt.html";
+
+addTest(async function testPermissionAllow() {
+  removePermission(testPageURL, "persistent-storage");
+
+  registerPopupEventHandler("popupshowing", function() {
+    ok(true, "prompt showing");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(true, "prompt shown");
+    triggerMainCommand(this);
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(true, "prompt hidden");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(true, gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.ALLOW_ACTION,
+    "Correct permission set"
+  );
+  gBrowser.removeCurrentTab();
+  unregisterAllPopupEventHandlers();
+  // Keep persistent-storage permission for the next test.
+});
+
+addTest(async function testNoPermissionPrompt() {
+  registerPopupEventHandler("popupshowing", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(true, gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.ALLOW_ACTION,
+    "Correct permission set"
+  );
+  gBrowser.removeCurrentTab();
+  unregisterAllPopupEventHandlers();
+  removePermission(testPageURL, "persistent-storage");
+});
diff --git a/dom/quota/test/browser/browser_permissionsPromptDeny.js b/dom/quota/test/browser/browser_permissionsPromptDeny.js
new file mode 100644
index 0000000000..19ee8ef499
--- /dev/null
+++ b/dom/quota/test/browser/browser_permissionsPromptDeny.js
@@ -0,0 +1,150 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const testPageURL =
+  "https://example.com/browser/dom/quota/test/browser/permissionsPrompt.html";
+
+addTest(async function testPermissionTemporaryDenied() {
+  registerPopupEventHandler("popupshowing", function() {
+    ok(true, "prompt showing");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(true, "prompt shown");
+    triggerSecondaryCommand(this);
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(true, "prompt hidden");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(false, gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "Correct permission set"
+  );
+
+  let tempBlock = SitePermissions.getAllForBrowser(
+    gBrowser.selectedBrowser
+  ).find(
+    p =>
+      p.id == "persistent-storage" &&
+      p.state == SitePermissions.BLOCK &&
+      p.scope == SitePermissions.SCOPE_TEMPORARY
+  );
+  ok(tempBlock, "Should have a temporary block permission on active browser");
+
+  unregisterAllPopupEventHandlers();
+  gBrowser.removeCurrentTab();
+  removePermission(testPageURL, "persistent-storage");
+});
+
+addTest(async function testPermissionDenied() {
+  removePermission(testPageURL, "persistent-storage");
+
+  registerPopupEventHandler("popupshowing", function() {
+    ok(true, "prompt showing");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(true, "prompt shown");
+    triggerSecondaryCommand(this, /* remember = */ true);
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(true, "prompt hidden");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(false, gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.DENY_ACTION,
+    "Correct permission set"
+  );
+  unregisterAllPopupEventHandlers();
+  gBrowser.removeCurrentTab();
+  // Keep persistent-storage permission for the next test.
+});
+
+addTest(async function testNoPermissionPrompt() {
+  registerPopupEventHandler("popupshowing", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(false, "Shouldn't show a popup this time");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(false, gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.DENY_ACTION,
+    "Correct permission set"
+  );
+  unregisterAllPopupEventHandlers();
+  gBrowser.removeCurrentTab();
+  removePermission(testPageURL, "persistent-storage");
+});
+
+addTest(async function testPermissionDeniedDismiss() {
+  registerPopupEventHandler("popupshowing", function() {
+    ok(true, "prompt showing");
+  });
+  registerPopupEventHandler("popupshown", function() {
+    ok(true, "prompt shown");
+    // Dismiss permission prompt.
+    dismissNotification(this);
+  });
+  registerPopupEventHandler("popuphidden", function() {
+    ok(true, "prompt hidden");
+  });
+
+  info("Creating tab");
+  gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(false, gBrowser);
+
+  // Pressing ESC results in a temporary block permission on the browser object.
+  // So the global permission for the URL should still be unknown, but the browser
+  // should have a block permission with a temporary scope.
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "Correct permission set"
+  );
+
+  let tempBlock = SitePermissions.getAllForBrowser(
+    gBrowser.selectedBrowser
+  ).find(
+    p =>
+      p.id == "persistent-storage" &&
+      p.state == SitePermissions.BLOCK &&
+      p.scope == SitePermissions.SCOPE_TEMPORARY
+  );
+  ok(tempBlock, "Should have a temporary block permission on active browser");
+
+  unregisterAllPopupEventHandlers();
+  gBrowser.removeCurrentTab();
+  removePermission(testPageURL, "persistent-storage");
+});
diff --git a/dom/quota/test/browser/browser_permissionsPromptUnknown.js b/dom/quota/test/browser/browser_permissionsPromptUnknown.js
new file mode 100644
index 0000000000..31c7e588a5
--- /dev/null
+++ b/dom/quota/test/browser/browser_permissionsPromptUnknown.js
@@ -0,0 +1,53 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const testPageURL =
+  "https://example.com/browser/dom/quota/test/browser/permissionsPrompt.html";
+
+addTest(async function testPermissionUnknownInPrivateWindow() {
+  removePermission(testPageURL, "persistent-storage");
+  info("Creating private window");
+  let win = await BrowserTestUtils.openNewBrowserWindow({ private: true });
+
+  registerPopupEventHandler(
+    "popupshowing",
+    function() {
+      ok(false, "Shouldn't show a popup this time");
+    },
+    win
+  );
+  registerPopupEventHandler(
+    "popupshown",
+    function() {
+      ok(false, "Shouldn't show a popup this time");
+    },
+    win
+  );
+  registerPopupEventHandler(
+    "popuphidden",
+    function() {
+      ok(false, "Shouldn't show a popup this time");
+    },
+    win
+  );
+
+  info("Creating private tab");
+  win.gBrowser.selectedTab = BrowserTestUtils.addTab(win.gBrowser);
+
+  info("Loading test page: " + testPageURL);
+  BrowserTestUtils.loadURI(win.gBrowser.selectedBrowser, testPageURL);
+  await waitForMessage(false, win.gBrowser);
+
+  is(
+    getPermission(testPageURL, "persistent-storage"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "Correct permission set"
+  );
+  unregisterAllPopupEventHandlers(win);
+  win.gBrowser.removeCurrentTab();
+  await BrowserTestUtils.closeWindow(win);
+  win = null;
+  removePermission(testPageURL, "persistent-storage");
+});
diff --git a/dom/quota/test/browser/browser_simpledb.js b/dom/quota/test/browser/browser_simpledb.js
new file mode 100644
index 0000000000..b3be78fca6
--- /dev/null
+++ b/dom/quota/test/browser/browser_simpledb.js
@@ -0,0 +1,51 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// getRandomBuffer, compareBuffers
+loadScript("dom/quota/test/common/file.js");
+
+addTest(async function testSimpleDB() {
+  const name = "data";
+  const bufferSize = 100;
+
+  let database = getSimpleDatabase();
+
+  let request = database.open("data");
+  await requestFinished(request);
+
+  let buffer1 = getRandomBuffer(bufferSize);
+
+  request = database.write(buffer1);
+  await requestFinished(request);
+
+  request = database.seek(0);
+  await requestFinished(request);
+
+  request = database.read(bufferSize);
+  let result = await requestFinished(request);
+
+  let buffer2 = result.getAsArrayBuffer();
+
+  ok(compareBuffers(buffer1, buffer2), "Buffers equal.");
+
+  let database2 = getSimpleDatabase();
+
+  try {
+    request = database2.open(name);
+    await requestFinished(request);
+    ok(false, "Should have thrown!");
+  } catch (ex) {
+    ok(request.resultCode == NS_ERROR_STORAGE_BUSY, "Good result code.");
+  }
+
+  request = database.close();
+  await requestFinished(request);
+
+  request = database2.open(name);
+  await requestFinished(request);
+
+  request = database2.close();
+  await requestFinished(request);
+});
diff --git a/dom/quota/test/browser/empty.html b/dom/quota/test/browser/empty.html
new file mode 100644
index 0000000000..1ad28bb1f7
--- /dev/null
+++ b/dom/quota/test/browser/empty.html
@@ -0,0 +1,8 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+<title>Empty file</title>
+</head>
+<body>
+</body>
+</html>
diff --git a/dom/quota/test/browser/head.js b/dom/quota/test/browser/head.js
new file mode 100644
index 0000000000..fd81168b02
--- /dev/null
+++ b/dom/quota/test/browser/head.js
@@ -0,0 +1,149 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../";
+
+var gActiveListeners = {};
+
+loadScript("dom/quota/test/common/browser.js");
+
+function loadScript(path) {
+  const url = new URL(depth + path, gTestPath);
+  Services.scriptloader.loadSubScript(url.href, this);
+}
+
+// These event (un)registration handlers only work for one window, DONOT use
+// them with multiple windows.
+
+function registerPopupEventHandler(eventName, callback, win) {
+  if (!win) {
+    win = window;
+  }
+  gActiveListeners[eventName] = function(event) {
+    if (event.target != win.PopupNotifications.panel) {
+      return;
+    }
+    win.PopupNotifications.panel.removeEventListener(
+      eventName,
+      gActiveListeners[eventName]
+    );
+    delete gActiveListeners[eventName];
+
+    callback.call(win.PopupNotifications.panel);
+  };
+  win.PopupNotifications.panel.addEventListener(
+    eventName,
+    gActiveListeners[eventName]
+  );
+}
+
+function unregisterAllPopupEventHandlers(win) {
+  if (!win) {
+    win = window;
+  }
+  for (let eventName in gActiveListeners) {
+    win.PopupNotifications.panel.removeEventListener(
+      eventName,
+      gActiveListeners[eventName]
+    );
+  }
+  gActiveListeners = {};
+}
+
+function triggerMainCommand(popup, win) {
+  if (!win) {
+    win = window;
+  }
+  info("triggering main command");
+  let notifications = popup.childNodes;
+  ok(notifications.length, "at least one notification displayed");
+  let notification = notifications[0];
+  info("triggering command: " + notification.getAttribute("buttonlabel"));
+
+  EventUtils.synthesizeMouseAtCenter(notification.button, {}, win);
+}
+
+async function triggerSecondaryCommand(popup, remember = false, win = window) {
+  info("triggering secondary command");
+  let notifications = popup.childNodes;
+  ok(notifications.length, "at least one notification displayed");
+  let notification = notifications[0];
+
+  if (remember) {
+    notification.checkbox.checked = true;
+  }
+
+  await EventUtils.synthesizeMouseAtCenter(
+    notification.secondaryButton,
+    {},
+    win
+  );
+}
+
+function dismissNotification(popup, win = window) {
+  info("dismissing notification");
+  executeSoon(function() {
+    EventUtils.synthesizeKey("VK_ESCAPE", {}, win);
+  });
+}
+
+function waitForMessage(aMessage, browser) {
+  // We cannot capture aMessage inside the checkFn, so we override the
+  // checkFn.toSource to tunnel aMessage instead.
+  let checkFn = function() {};
+  checkFn.toSource = function() {
+    return `function checkFn(event) {
+      let message = ${aMessage.toSource()};
+      if (event.data == message) {
+        return true;
+      }
+      throw new Error(
+       \`Unexpected result: \$\{event.data\}, expected \$\{message\}\`
+      );
+    }`;
+  };
+
+  return BrowserTestUtils.waitForContentEvent(
+    browser.selectedBrowser,
+    "message",
+    /* capture */ true,
+    checkFn,
+    /* wantsUntrusted */ true
+  ).then(() => {
+    // An assertion in checkFn wouldn't be recorded as part of the test, so we
+    // use this assertion to confirm that we've successfully received the
+    // message (we'll only reach this point if that's the case).
+    ok(true, "Received message: " + aMessage);
+  });
+}
+
+function removePermission(url, permission) {
+  let uri = Cc["@mozilla.org/network/io-service;1"]
+    .getService(Ci.nsIIOService)
+    .newURI(url);
+  let ssm = Cc["@mozilla.org/scriptsecuritymanager;1"].getService(
+    Ci.nsIScriptSecurityManager
+  );
+  let principal = ssm.createContentPrincipal(uri, {});
+
+  Cc["@mozilla.org/permissionmanager;1"]
+    .getService(Ci.nsIPermissionManager)
+    .removeFromPrincipal(principal, permission);
+}
+
+function getPermission(url, permission) {
+  let uri = Cc["@mozilla.org/network/io-service;1"]
+    .getService(Ci.nsIIOService)
+    .newURI(url);
+  let ssm = Cc["@mozilla.org/scriptsecuritymanager;1"].getService(
+    Ci.nsIScriptSecurityManager
+  );
+  let principal = ssm.createContentPrincipal(uri, {});
+
+  return Cc["@mozilla.org/permissionmanager;1"]
+    .getService(Ci.nsIPermissionManager)
+    .testPermissionFromPrincipal(principal, permission);
+}
diff --git a/dom/quota/test/browser/helpers.js b/dom/quota/test/browser/helpers.js
new file mode 100644
index 0000000000..f3bbb36b71
--- /dev/null
+++ b/dom/quota/test/browser/helpers.js
@@ -0,0 +1,46 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../";
+
+var testGenerator;
+var testResult;
+
+loadScript("dom/quota/test/common/nestedtest.js");
+
+function loadScript(path) {
+  const url = new URL(depth + path, window.location.href);
+  SpecialPowers.Services.scriptloader.loadSubScript(url.href, this);
+}
+
+function runTest() {
+  clearAllDatabases(() => {
+    testGenerator = testSteps();
+    testGenerator.next();
+  });
+}
+
+function finishTestNow() {
+  if (testGenerator) {
+    testGenerator.return();
+    testGenerator = undefined;
+  }
+}
+
+function finishTest() {
+  clearAllDatabases(() => {
+    setTimeout(finishTestNow, 0);
+    setTimeout(() => {
+      window.parent.postMessage(testResult, "*");
+    }, 0);
+  });
+}
+
+function continueToNextStep() {
+  setTimeout(() => {
+    testGenerator.next();
+  }, 0);
+}
diff --git a/dom/quota/test/browser/permissionsPrompt.html b/dom/quota/test/browser/permissionsPrompt.html
new file mode 100644
index 0000000000..5f11bf6c95
--- /dev/null
+++ b/dom/quota/test/browser/permissionsPrompt.html
@@ -0,0 +1,34 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+  <head>
+    <meta charset=UTF-8>
+    <title>Persistent-Storage Permission Prompt Test</title>
+
+    <script type="text/javascript" src="helpers.js"></script>
+
+    <script type="text/javascript">
+      function* testSteps()
+      {
+        SpecialPowers.pushPrefEnv({
+          "set": [["dom.storageManager.prompt.testing", false],
+                  ["dom.storageManager.prompt.testing.allow", false]]
+        }, continueToNextStep);
+        yield undefined;
+
+        navigator.storage.persist().then(result => {
+          testGenerator.next(result);
+        });
+        testResult = yield undefined;
+
+        finishTest();
+      }
+    </script>
+
+  </head>
+
+  <body onload="runTest();" onunload="finishTestNow();"></body>
+
+</html>
diff --git a/dom/quota/test/common/browser.js b/dom/quota/test/common/browser.js
new file mode 100644
index 0000000000..aae80adcd1
--- /dev/null
+++ b/dom/quota/test/common/browser.js
@@ -0,0 +1,34 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/system.js");
+
+function addTest(testFunction) {
+  const taskFunction = async function() {
+    await enableStorageTesting();
+
+    await testFunction();
+  };
+
+  Object.defineProperty(taskFunction, "name", {
+    value: testFunction.name,
+    writable: false,
+  });
+
+  add_task(taskFunction);
+}
+
+async function enableStorageTesting() {
+  const prefsToSet = [
+    ["dom.quotaManager.testing", true],
+    ["dom.storageManager.enabled", true],
+    ["dom.simpleDB.enabled", true],
+  ];
+  if (Services.appinfo.OS === "WINNT") {
+    prefsToSet.push(["dom.quotaManager.useDOSDevicePathSyntax", true]);
+  }
+
+  await SpecialPowers.pushPrefEnv({ set: prefsToSet });
+}
diff --git a/dom/quota/test/common/content.js b/dom/quota/test/common/content.js
new file mode 100644
index 0000000000..d3927d649a
--- /dev/null
+++ b/dom/quota/test/common/content.js
@@ -0,0 +1,62 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const NS_ERROR_STORAGE_BUSY = SpecialPowers.Cr.NS_ERROR_STORAGE_BUSY;
+
+loadScript("dom/quota/test/common/global.js");
+
+function clearAllDatabases(callback) {
+  let qms = SpecialPowers.Services.qms;
+  let principal = SpecialPowers.wrap(document).nodePrincipal;
+  let request = qms.clearStoragesForPrincipal(principal);
+  let cb = SpecialPowers.wrapCallback(callback);
+  request.callback = cb;
+  return request;
+}
+
+// SimpleDB connections and SpecialPowers wrapping:
+//
+// SpecialPowers provides a SpecialPowersHandler Proxy mechanism that lets our
+// content-privileged code borrow its chrome-privileged principal to access
+// things we shouldn't be able to access.  The proxies wrap their returned
+// values, so once we have something wrapped we can rely on returned objects
+// being wrapped as well.  The proxy will also automatically unwrap wrapped
+// arguments we pass in.  However, we need to invoke wrapCallback on callback
+// functions so that the arguments they receive will be wrapped because the
+// proxy does not automatically wrap content-privileged functions.
+//
+// Our use of (wrapped) SpecialPowers.Cc results in getSimpleDatabase()
+// producing a wrapped nsISDBConnection instance.  The nsISDBResult instances
+// exposed on the (wrapped) nsISDBRequest are also wrapped.
+// In particular, the wrapper takes responsibility for automatically cloning
+// the ArrayBuffer returned by nsISDBResult.getAsArrayBuffer into the content
+// compartment (rather than wrapping it) so that constructing a Uint8Array
+// from it will succeed.
+
+function getSimpleDatabase() {
+  let connection = SpecialPowers.Cc[
+    "@mozilla.org/dom/sdb-connection;1"
+  ].createInstance(SpecialPowers.Ci.nsISDBConnection);
+
+  let principal = SpecialPowers.wrap(document).nodePrincipal;
+
+  connection.init(principal);
+
+  return connection;
+}
+
+async function requestFinished(request) {
+  await new Promise(function(resolve) {
+    request.callback = SpecialPowers.wrapCallback(function() {
+      resolve();
+    });
+  });
+
+  if (request.resultCode != SpecialPowers.Cr.NS_OK) {
+    throw new RequestError(request.resultCode, request.resultName);
+  }
+
+  return request.result;
+}
diff --git a/dom/quota/test/common/file.js b/dom/quota/test/common/file.js
new file mode 100644
index 0000000000..55e2e189fb
--- /dev/null
+++ b/dom/quota/test/common/file.js
@@ -0,0 +1,45 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function getBuffer(size) {
+  let buffer = new ArrayBuffer(size);
+  is(buffer.byteLength, size, "Correct byte length");
+  return buffer;
+}
+
+// May be called for any size, but you should call getBuffer() if you know
+// that size is big and that randomness is not necessary because it is
+// noticeably faster.
+function getRandomBuffer(size) {
+  let buffer = getBuffer(size);
+  let view = new Uint8Array(buffer);
+  for (let i = 0; i < size; i++) {
+    view[i] = parseInt(Math.random() * 255);
+  }
+  return buffer;
+}
+
+function compareBuffers(buffer1, buffer2) {
+  if (buffer1.byteLength != buffer2.byteLength) {
+    return false;
+  }
+
+  let view1 = buffer1 instanceof Uint8Array ? buffer1 : new Uint8Array(buffer1);
+  let view2 = buffer2 instanceof Uint8Array ? buffer2 : new Uint8Array(buffer2);
+  for (let i = 0; i < buffer1.byteLength; i++) {
+    if (view1[i] != view2[i]) {
+      return false;
+    }
+  }
+  return true;
+}
+
+function getBlob(type, object) {
+  return new Blob([object], { type });
+}
+
+function getNullBlob(size) {
+  return getBlob("binary/null", getBuffer(size));
+}
diff --git a/dom/quota/test/common/global.js b/dom/quota/test/common/global.js
new file mode 100644
index 0000000000..bb0f3669be
--- /dev/null
+++ b/dom/quota/test/common/global.js
@@ -0,0 +1,47 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const INT64_MIN = -0x8000000000000000n;
+
+class RequestError extends Error {
+  constructor(resultCode, resultName) {
+    super(`Request failed (code: ${resultCode}, name: ${resultName})`);
+    this.name = "RequestError";
+    this.resultCode = resultCode;
+    this.resultName = resultName;
+  }
+}
+
+function openDBRequestUpgradeNeeded(request) {
+  return new Promise(function(resolve, reject) {
+    request.onerror = function(event) {
+      ok(false, "indexedDB error, '" + event.target.error.name + "'");
+      reject(event);
+    };
+    request.onupgradeneeded = function(event) {
+      resolve(event);
+    };
+    request.onsuccess = function(event) {
+      ok(false, "Got success, but did not expect it!");
+      reject(event);
+    };
+  });
+}
+
+function openDBRequestSucceeded(request) {
+  return new Promise(function(resolve, reject) {
+    request.onerror = function(event) {
+      ok(false, "indexedDB error, '" + event.target.error.name + "'");
+      reject(event);
+    };
+    request.onupgradeneeded = function(event) {
+      ok(false, "Got upgrade, but did not expect it!");
+      reject(event);
+    };
+    request.onsuccess = function(event) {
+      resolve(event);
+    };
+  });
+}
diff --git a/dom/quota/test/common/mochitest.js b/dom/quota/test/common/mochitest.js
new file mode 100644
index 0000000000..1b867f6e92
--- /dev/null
+++ b/dom/quota/test/common/mochitest.js
@@ -0,0 +1,19 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/content.js");
+
+async function enableStorageTesting() {
+  let prefsToSet = [
+    ["dom.quotaManager.testing", true],
+    ["dom.storageManager.enabled", true],
+    ["dom.simpleDB.enabled", true],
+  ];
+  if (SpecialPowers.Services.appinfo.OS === "WINNT") {
+    prefsToSet.push(["dom.quotaManager.useDOSDevicePathSyntax", true]);
+  }
+
+  await SpecialPowers.pushPrefEnv({ set: prefsToSet });
+}
diff --git a/dom/quota/test/common/nestedtest.js b/dom/quota/test/common/nestedtest.js
new file mode 100644
index 0000000000..5c2011bfe9
--- /dev/null
+++ b/dom/quota/test/common/nestedtest.js
@@ -0,0 +1,6 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/content.js");
diff --git a/dom/quota/test/common/system.js b/dom/quota/test/common/system.js
new file mode 100644
index 0000000000..25acbe9384
--- /dev/null
+++ b/dom/quota/test/common/system.js
@@ -0,0 +1,74 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const PR_USEC_PER_SEC = 1000000;
+
+const NS_ERROR_STORAGE_BUSY = Cr.NS_ERROR_STORAGE_BUSY;
+
+loadScript("dom/quota/test/common/global.js");
+
+function getProfileDir() {
+  return Services.dirsvc.get("ProfD", Ci.nsIFile);
+}
+
+// Given a "/"-delimited path relative to a base file (or the profile
+// directory if a base file is not provided) return an nsIFile representing the
+// path.  This does not test for the existence of the file or parent
+// directories.  It is safe even on Windows where the directory separator is
+// not "/", but make sure you're not passing in a "\"-delimited path.
+function getRelativeFile(relativePath, baseFile) {
+  if (!baseFile) {
+    baseFile = getProfileDir();
+  }
+
+  let file = baseFile.clone();
+
+  if (Services.appinfo.OS === "WINNT") {
+    let winFile = file.QueryInterface(Ci.nsILocalFileWin);
+    winFile.useDOSDevicePathSyntax = true;
+  }
+
+  relativePath.split("/").forEach(function(component) {
+    if (component == "..") {
+      file = file.parent;
+    } else {
+      file.append(component);
+    }
+  });
+
+  return file;
+}
+
+function getCurrentPrincipal() {
+  return Cc["@mozilla.org/systemprincipal;1"].createInstance(Ci.nsIPrincipal);
+}
+
+function getSimpleDatabase(principal, persistence) {
+  let connection = Cc["@mozilla.org/dom/sdb-connection;1"].createInstance(
+    Ci.nsISDBConnection
+  );
+
+  if (!principal) {
+    principal = getCurrentPrincipal();
+  }
+
+  connection.init(principal, persistence);
+
+  return connection;
+}
+
+async function requestFinished(request) {
+  await new Promise(function(resolve) {
+    request.callback = function() {
+      resolve();
+    };
+  });
+
+  if (request.resultCode !== Cr.NS_OK) {
+    throw new RequestError(request.resultCode, request.resultName);
+  }
+
+  return request.result;
+}
diff --git a/dom/quota/test/common/test_simpledb.js b/dom/quota/test/common/test_simpledb.js
new file mode 100644
index 0000000000..dee7019097
--- /dev/null
+++ b/dom/quota/test/common/test_simpledb.js
@@ -0,0 +1,50 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+async function testSteps() {
+  const name = "data";
+  const bufferSize = 100;
+
+  let database = getSimpleDatabase();
+
+  let request = database.open(name);
+  await requestFinished(request);
+
+  let buffer1 = getRandomBuffer(bufferSize);
+
+  request = database.write(buffer1);
+  await requestFinished(request);
+
+  request = database.seek(0);
+  await requestFinished(request);
+
+  request = database.read(bufferSize);
+  let result = await requestFinished(request);
+
+  let buffer2 = result.getAsArrayBuffer();
+
+  ok(compareBuffers(buffer1, buffer2), "Buffers equal.");
+
+  let database2 = getSimpleDatabase();
+
+  try {
+    request = database2.open(name);
+    await requestFinished(request);
+    ok(false, "Should have thrown!");
+  } catch (ex) {
+    ok(request.resultCode == NS_ERROR_STORAGE_BUSY, "Good result code.");
+  }
+
+  request = database.close();
+  await requestFinished(request);
+
+  request = database2.open(name);
+  await requestFinished(request);
+
+  request = database2.close();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/common/test_storage_manager_persist_allow.js b/dom/quota/test/common/test_storage_manager_persist_allow.js
new file mode 100644
index 0000000000..0a6e59843d
--- /dev/null
+++ b/dom/quota/test/common/test_storage_manager_persist_allow.js
@@ -0,0 +1,30 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  SpecialPowers.pushPrefEnv(
+    {
+      set: [["dom.storageManager.prompt.testing.allow", true]],
+    },
+    continueToNextStep
+  );
+  yield undefined;
+
+  navigator.storage.persist().then(grabArgAndContinueHandler);
+  let persistResult = yield undefined;
+
+  is(persistResult, true, "Persist succeeded");
+
+  navigator.storage.persisted().then(grabArgAndContinueHandler);
+  let persistedResult = yield undefined;
+
+  is(
+    persistResult,
+    persistedResult,
+    "Persist/persisted results are consistent"
+  );
+
+  finishTest();
+}
diff --git a/dom/quota/test/common/test_storage_manager_persist_deny.js b/dom/quota/test/common/test_storage_manager_persist_deny.js
new file mode 100644
index 0000000000..855d739ca3
--- /dev/null
+++ b/dom/quota/test/common/test_storage_manager_persist_deny.js
@@ -0,0 +1,34 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  SpecialPowers.pushPrefEnv(
+    {
+      set: [["dom.storageManager.prompt.testing.allow", false]],
+    },
+    continueToNextStep
+  );
+  yield undefined;
+
+  navigator.storage.persist().then(grabArgAndContinueHandler);
+  let persistResult = yield undefined;
+
+  is(
+    persistResult,
+    false,
+    "Cancel the persist prompt and resolve a promise with false"
+  );
+
+  navigator.storage.persisted().then(grabArgAndContinueHandler);
+  let persistedResult = yield undefined;
+
+  is(
+    persistResult,
+    persistedResult,
+    "Persist/persisted results are consistent"
+  );
+
+  finishTest();
+}
diff --git a/dom/quota/test/common/test_storage_manager_persisted.js b/dom/quota/test/common/test_storage_manager_persisted.js
new file mode 100644
index 0000000000..ebda93649a
--- /dev/null
+++ b/dom/quota/test/common/test_storage_manager_persisted.js
@@ -0,0 +1,13 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  navigator.storage.persisted().then(grabArgAndContinueHandler);
+  let persistedResult = yield undefined;
+
+  is(persistedResult, false, "Persisted returns false");
+
+  finishTest();
+}
diff --git a/dom/quota/test/common/xpcshell.js b/dom/quota/test/common/xpcshell.js
new file mode 100644
index 0000000000..ed3afaa467
--- /dev/null
+++ b/dom/quota/test/common/xpcshell.js
@@ -0,0 +1,91 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/system.js");
+
+function enableStorageTesting() {
+  Services.prefs.setBoolPref("dom.quotaManager.testing", true);
+  Services.prefs.setBoolPref("dom.storageManager.enabled", true);
+  Services.prefs.setBoolPref("dom.simpleDB.enabled", true);
+  if (Services.appinfo.OS === "WINNT") {
+    Services.prefs.setBoolPref("dom.quotaManager.useDOSDevicePathSyntax", true);
+  }
+}
+
+function resetStorageTesting() {
+  Services.prefs.clearUserPref("dom.quotaManager.testing");
+  Services.prefs.clearUserPref("dom.storageManager.enabled");
+  Services.prefs.clearUserPref("dom.simpleDB.enabled");
+  if (Services.appinfo.OS === "WINNT") {
+    Services.prefs.clearUserPref("dom.quotaManager.useDOSDevicePathSyntax");
+  }
+}
+
+function clear(callback) {
+  let request = Services.qms.clear();
+  request.callback = callback;
+
+  return request;
+}
+
+function reset(callback) {
+  let request = Services.qms.reset();
+  request.callback = callback;
+
+  return request;
+}
+
+function installPackage(packageRelativePath, allowFileOverwrites) {
+  let currentDir = Services.dirsvc.get("CurWorkD", Ci.nsIFile);
+
+  let packageFile = getRelativeFile(packageRelativePath + ".zip", currentDir);
+
+  let zipReader = Cc["@mozilla.org/libjar/zip-reader;1"].createInstance(
+    Ci.nsIZipReader
+  );
+  zipReader.open(packageFile);
+
+  let entryNames = Array.from(zipReader.findEntries(null));
+  entryNames.sort();
+
+  for (let entryName of entryNames) {
+    if (entryName.match(/^create_db\.(html|js)/)) {
+      continue;
+    }
+
+    let zipentry = zipReader.getEntry(entryName);
+
+    let file = getRelativeFile(entryName);
+
+    if (zipentry.isDirectory) {
+      if (!file.exists()) {
+        file.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+      }
+    } else {
+      if (!allowFileOverwrites && file.exists()) {
+        throw new Error("File already exists!");
+      }
+
+      let istream = zipReader.getInputStream(entryName);
+
+      var ostream = Cc[
+        "@mozilla.org/network/file-output-stream;1"
+      ].createInstance(Ci.nsIFileOutputStream);
+      ostream.init(file, -1, parseInt("0644", 8), 0);
+
+      let bostream = Cc[
+        "@mozilla.org/network/buffered-output-stream;1"
+      ].createInstance(Ci.nsIBufferedOutputStream);
+      bostream.init(ostream, 32768);
+
+      bostream.writeFrom(istream, istream.available());
+
+      istream.close();
+      bostream.close();
+    }
+  }
+
+  zipReader.close();
+}
diff --git a/dom/quota/test/gtest/Common.cpp b/dom/quota/test/gtest/Common.cpp
new file mode 100644
index 0000000000..efbfd94775
--- /dev/null
+++ b/dom/quota/test/gtest/Common.cpp
@@ -0,0 +1,28 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Common.h"
+
+#include "mozilla/dom/QMResult.h"
+
+namespace mozilla::dom::quota {
+
+#ifdef QM_ERROR_STACKS_ENABLED
+uint64_t DOM_Quota_Test::sExpectedStackId;
+
+// static
+void DOM_Quota_Test::SetUpTestCase() {
+  sExpectedStackId = QMResult().StackId();
+}
+
+// static
+void DOM_Quota_Test::IncreaseExpectedStackId() { sExpectedStackId++; }
+
+// static
+uint64_t DOM_Quota_Test::ExpectedStackId() { return sExpectedStackId; }
+#endif
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/test/gtest/Common.h b/dom/quota/test/gtest/Common.h
new file mode 100644
index 0000000000..eac58bd7fb
--- /dev/null
+++ b/dom/quota/test/gtest/Common.h
@@ -0,0 +1,32 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_TEST_GTEST_COMMON_H_
+#define DOM_QUOTA_TEST_GTEST_COMMON_H_
+
+#include <cstdint>
+#include "gtest/gtest.h"
+#include "mozilla/dom/quota/Config.h"
+
+namespace mozilla::dom::quota {
+
+class DOM_Quota_Test : public testing::Test {
+#ifdef QM_ERROR_STACKS_ENABLED
+ public:
+  static void SetUpTestCase();
+
+  static void IncreaseExpectedStackId();
+
+  static uint64_t ExpectedStackId();
+
+ private:
+  static uint64_t sExpectedStackId;
+#endif
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_TEST_GTEST_COMMON_H_
diff --git a/dom/quota/test/gtest/PQuotaTest.ipdl b/dom/quota/test/gtest/PQuotaTest.ipdl
new file mode 100644
index 0000000000..e4ca37325a
--- /dev/null
+++ b/dom/quota/test/gtest/PQuotaTest.ipdl
@@ -0,0 +1,26 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+namespace mozilla {
+namespace dom {
+namespace quota {
+
+sync protocol PQuotaTest {
+ parent:
+  sync Try_Success_CustomErr_QmIpcFail()
+    returns (bool tryDidNotReturn);
+
+  sync Try_Success_CustomErr_IpcFail()
+    returns (bool tryDidNotReturn);
+
+  sync TryInspect_Success_CustomErr_QmIpcFail()
+    returns (bool tryDidNotReturn);
+
+  sync TryInspect_Success_CustomErr_IpcFail()
+    returns (bool tryDidNotReturn);
+};
+
+} // namespace quota
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/quota/test/gtest/QuotaManagerDependencyFixture.cpp b/dom/quota/test/gtest/QuotaManagerDependencyFixture.cpp
new file mode 100644
index 0000000000..2e52b4b69a
--- /dev/null
+++ b/dom/quota/test/gtest/QuotaManagerDependencyFixture.cpp
@@ -0,0 +1,160 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "QuotaManagerDependencyFixture.h"
+
+#include "mozIStorageService.h"
+#include "mozStorageCID.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "mozilla/dom/quota/QuotaManagerService.h"
+#include "mozilla/gtest/MozAssertions.h"
+#include "nsIPrefBranch.h"
+#include "nsIPrefService.h"
+#include "nsIQuotaCallbacks.h"
+#include "nsIQuotaRequests.h"
+#include "nsIVariant.h"
+#include "nsScriptSecurityManager.h"
+
+namespace mozilla::dom::quota::test {
+
+namespace {
+
+class RequestResolver final : public nsIQuotaCallback {
+ public:
+  RequestResolver() : mDone(false) {}
+
+  bool Done() const { return mDone; }
+
+  NS_DECL_ISUPPORTS
+
+  NS_IMETHOD OnComplete(nsIQuotaRequest* aRequest) override {
+    mDone = true;
+
+    return NS_OK;
+  }
+
+ private:
+  ~RequestResolver() = default;
+
+  bool mDone;
+};
+
+}  // namespace
+
+NS_IMPL_ISUPPORTS(RequestResolver, nsIQuotaCallback)
+
+// static
+void QuotaManagerDependencyFixture::InitializeFixture() {
+  // Some QuotaManagerService methods fail if the testing pref is not set.
+  nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
+
+  prefs->SetBoolPref("dom.quotaManager.testing", true);
+
+  // The first initialization of storage service must be done on the main
+  // thread.
+  nsCOMPtr<mozIStorageService> storageService =
+      do_GetService(MOZ_STORAGE_SERVICE_CONTRACTID);
+  ASSERT_TRUE(storageService);
+
+  nsIObserver* observer = QuotaManager::GetObserver();
+  ASSERT_TRUE(observer);
+
+  nsresult rv = observer->Observe(nullptr, "profile-do-change", nullptr);
+  ASSERT_NS_SUCCEEDED(rv);
+
+  ASSERT_NO_FATAL_FAILURE(StorageInitialized());
+
+  QuotaManager* quotaManager = QuotaManager::Get();
+  ASSERT_TRUE(quotaManager);
+
+  ASSERT_TRUE(quotaManager->OwningThread());
+
+  sBackgroundTarget = quotaManager->OwningThread();
+}
+
+// static
+void QuotaManagerDependencyFixture::ShutdownFixture() {
+  nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
+
+  prefs->SetBoolPref("dom.quotaManager.testing", false);
+
+  nsIObserver* observer = QuotaManager::GetObserver();
+  ASSERT_TRUE(observer);
+
+  nsresult rv = observer->Observe(nullptr, "profile-before-change-qm", nullptr);
+  ASSERT_NS_SUCCEEDED(rv);
+
+  PerformOnBackgroundThread([]() { QuotaManager::Reset(); });
+
+  sBackgroundTarget = nullptr;
+}
+
+// static
+void QuotaManagerDependencyFixture::StorageInitialized(bool* aResult) {
+  AutoJSAPI jsapi;
+
+  bool ok = jsapi.Init(xpc::PrivilegedJunkScope());
+  ASSERT_TRUE(ok);
+
+  nsCOMPtr<nsIQuotaManagerService> qms = QuotaManagerService::GetOrCreate();
+  ASSERT_TRUE(qms);
+
+  nsCOMPtr<nsIQuotaRequest> request;
+  nsresult rv = qms->StorageInitialized(getter_AddRefs(request));
+  ASSERT_NS_SUCCEEDED(rv);
+
+  RefPtr<RequestResolver> resolver = new RequestResolver();
+
+  rv = request->SetCallback(resolver);
+  ASSERT_NS_SUCCEEDED(rv);
+
+  SpinEventLoopUntil("Promise is fulfilled"_ns,
+                     [&resolver]() { return resolver->Done(); });
+
+  if (aResult) {
+    nsCOMPtr<nsIVariant> result;
+    rv = request->GetResult(getter_AddRefs(result));
+    ASSERT_NS_SUCCEEDED(rv);
+
+    rv = result->GetAsBool(aResult);
+    ASSERT_NS_SUCCEEDED(rv);
+  }
+}
+
+// static
+void QuotaManagerDependencyFixture::ClearStoragesForOrigin(
+    const OriginMetadata& aOriginMetadata) {
+  nsCOMPtr<nsIQuotaManagerService> qms = QuotaManagerService::GetOrCreate();
+  ASSERT_TRUE(qms);
+
+  nsCOMPtr<nsIScriptSecurityManager> ssm =
+      nsScriptSecurityManager::GetScriptSecurityManager();
+  ASSERT_TRUE(ssm);
+
+  nsCOMPtr<nsIPrincipal> principal;
+  nsresult rv = ssm->CreateContentPrincipalFromOrigin(
+      aOriginMetadata.mOrigin, getter_AddRefs(principal));
+  ASSERT_NS_SUCCEEDED(rv);
+
+  nsCOMPtr<nsIQuotaRequest> request;
+  rv = qms->ClearStoragesForPrincipal(principal, VoidCString(), VoidString(),
+                                      /* aClearAll */ false,
+                                      getter_AddRefs(request));
+  ASSERT_NS_SUCCEEDED(rv);
+
+  RefPtr<RequestResolver> resolver = new RequestResolver();
+  ASSERT_TRUE(resolver);
+
+  rv = request->SetCallback(resolver);
+  ASSERT_NS_SUCCEEDED(rv);
+
+  SpinEventLoopUntil("Promise is fulfilled"_ns,
+                     [&resolver]() { return resolver->Done(); });
+}
+
+nsCOMPtr<nsISerialEventTarget> QuotaManagerDependencyFixture::sBackgroundTarget;
+
+}  // namespace mozilla::dom::quota::test
diff --git a/dom/quota/test/gtest/QuotaManagerDependencyFixture.h b/dom/quota/test/gtest/QuotaManagerDependencyFixture.h
new file mode 100644
index 0000000000..4d57952242
--- /dev/null
+++ b/dom/quota/test/gtest/QuotaManagerDependencyFixture.h
@@ -0,0 +1,87 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_TEST_GTEST_QUOTAMANAGERDEPENDENCYFIXTURE_H_
+#define DOM_QUOTA_TEST_GTEST_QUOTAMANAGERDEPENDENCYFIXTURE_H_
+
+#include "gtest/gtest.h"
+#include "mozilla/MozPromise.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "mozilla/dom/quota/ForwardDecls.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+
+namespace mozilla::dom::quota::test {
+
+class QuotaManagerDependencyFixture : public testing::Test {
+ public:
+ protected:
+  static void InitializeFixture();
+
+  static void ShutdownFixture();
+
+  static void StorageInitialized(bool* aResult = nullptr);
+
+  static void ClearStoragesForOrigin(const OriginMetadata& aOriginMetadata);
+
+  /* Convenience method for tasks which must be called on PBackground thread */
+  template <class Invokable, class... Args>
+  static void PerformOnBackgroundThread(Invokable&& aInvokable,
+                                        Args&&... aArgs) {
+    bool done = false;
+    auto boundTask =
+        // For c++17, bind is cleaner than tuple for parameter pack forwarding
+        // NOLINTNEXTLINE(modernize-avoid-bind)
+        std::bind(std::forward<Invokable>(aInvokable),
+                  std::forward<Args>(aArgs)...);
+    InvokeAsync(BackgroundTargetStrongRef(), __func__,
+                [boundTask = std::move(boundTask)] {
+                  boundTask();
+                  return BoolPromise::CreateAndResolve(true, __func__);
+                })
+        ->Then(GetCurrentSerialEventTarget(), __func__,
+               [&done](const BoolPromise::ResolveOrRejectValue& /* aValue */) {
+                 done = true;
+               });
+
+    SpinEventLoopUntil("Promise is fulfilled"_ns, [&done]() { return done; });
+  }
+
+  /* Convenience method for tasks which must be executed on IO thread */
+  template <class Invokable, class... Args>
+  static void PerformOnIOThread(Invokable&& aInvokable, Args&&... aArgs) {
+    QuotaManager* quotaManager = QuotaManager::Get();
+    ASSERT_TRUE(quotaManager);
+
+    bool done = false;
+    auto boundTask =
+        // For c++17, bind is cleaner than tuple for parameter pack forwarding
+        // NOLINTNEXTLINE(modernize-avoid-bind)
+        std::bind(std::forward<Invokable>(aInvokable),
+                  std::forward<Args>(aArgs)...);
+    InvokeAsync(quotaManager->IOThread(), __func__,
+                [boundTask = std::move(boundTask)]() {
+                  boundTask();
+                  return BoolPromise::CreateAndResolve(true, __func__);
+                })
+        ->Then(GetCurrentSerialEventTarget(), __func__,
+               [&done](const BoolPromise::ResolveOrRejectValue& value) {
+                 done = true;
+               });
+
+    SpinEventLoopUntil("Promise is fulfilled"_ns, [&done]() { return done; });
+  }
+
+  static const nsCOMPtr<nsISerialEventTarget>& BackgroundTargetStrongRef() {
+    return sBackgroundTarget;
+  }
+
+ private:
+  static nsCOMPtr<nsISerialEventTarget> sBackgroundTarget;
+};
+
+}  // namespace mozilla::dom::quota::test
+
+#endif  // DOM_QUOTA_TEST_GTEST_QUOTAMANAGERDEPENDENCYFIXTURE_H_
diff --git a/dom/quota/test/gtest/QuotaTestChild.h b/dom/quota/test/gtest/QuotaTestChild.h
new file mode 100644
index 0000000000..d0d87d8267
--- /dev/null
+++ b/dom/quota/test/gtest/QuotaTestChild.h
@@ -0,0 +1,23 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_TEST_GTEST_QUOTATESTCHILD_H_
+#define DOM_QUOTA_TEST_GTEST_QUOTATESTCHILD_H_
+
+#include "mozilla/dom/quota/PQuotaTestChild.h"
+
+namespace mozilla::dom::quota {
+
+class QuotaTestChild : public PQuotaTestChild {
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(QuotaTestChild, override)
+
+ private:
+  ~QuotaTestChild() = default;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_TEST_GTEST_QUOTATESTCHILD_H_
diff --git a/dom/quota/test/gtest/QuotaTestParent.h b/dom/quota/test/gtest/QuotaTestParent.h
new file mode 100644
index 0000000000..5ec1e128b3
--- /dev/null
+++ b/dom/quota/test/gtest/QuotaTestParent.h
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_QUOTA_TEST_GTEST_QUOTATESTPARENT_H_
+#define DOM_QUOTA_TEST_GTEST_QUOTATESTPARENT_H_
+
+#include "mozilla/dom/quota/PQuotaTestParent.h"
+
+namespace mozilla::dom::quota {
+
+class QuotaTestParent : public PQuotaTestParent {
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(QuotaTestParent, override)
+
+ public:
+  mozilla::ipc::IPCResult RecvTry_Success_CustomErr_QmIpcFail(
+      bool* aTryDidNotReturn);
+
+  mozilla::ipc::IPCResult RecvTry_Success_CustomErr_IpcFail(
+      bool* aTryDidNotReturn);
+
+  mozilla::ipc::IPCResult RecvTryInspect_Success_CustomErr_QmIpcFail(
+      bool* aTryDidNotReturn);
+
+  mozilla::ipc::IPCResult RecvTryInspect_Success_CustomErr_IpcFail(
+      bool* aTryDidNotReturn);
+
+ private:
+  ~QuotaTestParent() = default;
+};
+
+}  // namespace mozilla::dom::quota
+
+#endif  // DOM_QUOTA_TEST_GTEST_QUOTATESTPARENT_H_
diff --git a/dom/quota/test/gtest/TestCheckedUnsafePtr.cpp b/dom/quota/test/gtest/TestCheckedUnsafePtr.cpp
new file mode 100644
index 0000000000..14abb6631d
--- /dev/null
+++ b/dom/quota/test/gtest/TestCheckedUnsafePtr.cpp
@@ -0,0 +1,145 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/CheckedUnsafePtr.h"
+
+#include "gtest/gtest.h"
+
+#include <memory>
+#include <type_traits>
+#include <utility>
+#include "mozilla/fallible.h"
+
+using namespace mozilla;
+
+class NoCheckTestType
+    : public SupportsCheckedUnsafePtr<DoNotCheckCheckedUnsafePtrs> {};
+
+#if __cplusplus < 202002L
+static_assert(std::is_literal_type_v<CheckedUnsafePtr<NoCheckTestType>>);
+#endif
+
+static_assert(
+    std::is_trivially_copy_constructible_v<CheckedUnsafePtr<NoCheckTestType>>);
+static_assert(
+    std::is_trivially_copy_assignable_v<CheckedUnsafePtr<NoCheckTestType>>);
+static_assert(
+    std::is_trivially_move_constructible_v<CheckedUnsafePtr<NoCheckTestType>>);
+static_assert(
+    std::is_trivially_move_assignable_v<CheckedUnsafePtr<NoCheckTestType>>);
+
+class TestCheckingPolicy : public CheckCheckedUnsafePtrs<TestCheckingPolicy> {
+ protected:
+  explicit TestCheckingPolicy(bool& aPassedCheck)
+      : mPassedCheck(aPassedCheck) {}
+
+ private:
+  friend class mozilla::CheckingPolicyAccess;
+  void NotifyCheckFailure() { mPassedCheck = false; }
+
+  bool& mPassedCheck;
+};
+
+struct BasePointee : public SupportsCheckedUnsafePtr<TestCheckingPolicy> {
+  explicit BasePointee(bool& aCheckPassed)
+      : SupportsCheckedUnsafePtr<TestCheckingPolicy>(aCheckPassed) {}
+};
+
+struct DerivedPointee : public BasePointee {
+  using BasePointee::BasePointee;
+};
+
+class CheckedUnsafePtrTest : public ::testing::Test {
+ protected:
+  bool mPassedCheck = true;
+};
+
+TEST_F(CheckedUnsafePtrTest, PointeeWithNoCheckedUnsafePtrs) {
+  { DerivedPointee pointee{mPassedCheck}; }
+  ASSERT_TRUE(mPassedCheck);
+}
+
+template <typename PointerType>
+class TypedCheckedUnsafePtrTest : public CheckedUnsafePtrTest {};
+
+TYPED_TEST_SUITE_P(TypedCheckedUnsafePtrTest);
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest, PointeeWithOneCheckedUnsafePtr) {
+  {
+    DerivedPointee pointee{this->mPassedCheck};
+    CheckedUnsafePtr<TypeParam> ptr = &pointee;
+  }
+  ASSERT_TRUE(this->mPassedCheck);
+}
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest, CheckedUnsafePtrCopyConstructed) {
+  {
+    DerivedPointee pointee{this->mPassedCheck};
+    CheckedUnsafePtr<TypeParam> ptr1 = &pointee;
+    CheckedUnsafePtr<TypeParam> ptr2 = ptr1;
+  }
+  ASSERT_TRUE(this->mPassedCheck);
+}
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest, CheckedUnsafePtrCopyAssigned) {
+  {
+    DerivedPointee pointee{this->mPassedCheck};
+    CheckedUnsafePtr<TypeParam> ptr1 = &pointee;
+    CheckedUnsafePtr<TypeParam> ptr2;
+    ptr2 = ptr1;
+  }
+  ASSERT_TRUE(this->mPassedCheck);
+}
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest,
+             PointeeWithOneDanglingCheckedUnsafePtr) {
+  [this]() -> CheckedUnsafePtr<TypeParam> {
+    DerivedPointee pointee{this->mPassedCheck};
+    return &pointee;
+  }();
+  ASSERT_FALSE(this->mPassedCheck);
+}
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest,
+             PointeeWithOneCopiedDanglingCheckedUnsafePtr) {
+  const auto dangling1 = [this]() -> CheckedUnsafePtr<DerivedPointee> {
+    DerivedPointee pointee{this->mPassedCheck};
+    return &pointee;
+  }();
+  EXPECT_FALSE(this->mPassedCheck);
+
+  // With AddressSanitizer we would hopefully detect if the copy constructor
+  // tries to add dangling2 to the now-gone pointee's unsafe pointer array. No
+  // promises though, since it might be optimized away.
+  CheckedUnsafePtr<TypeParam> dangling2{dangling1};
+  ASSERT_TRUE(dangling2);
+}
+
+TYPED_TEST_P(TypedCheckedUnsafePtrTest,
+             PointeeWithOneCopyAssignedDanglingCheckedUnsafePtr) {
+  const auto dangling1 = [this]() -> CheckedUnsafePtr<DerivedPointee> {
+    DerivedPointee pointee{this->mPassedCheck};
+    return &pointee;
+  }();
+  EXPECT_FALSE(this->mPassedCheck);
+
+  // With AddressSanitizer we would hopefully detect if the assignment tries to
+  // add dangling2 to the now-gone pointee's unsafe pointer array. No promises
+  // though, since it might be optimized away.
+  CheckedUnsafePtr<TypeParam> dangling2;
+  dangling2 = dangling1;
+  ASSERT_TRUE(dangling2);
+}
+
+REGISTER_TYPED_TEST_SUITE_P(TypedCheckedUnsafePtrTest,
+                            PointeeWithOneCheckedUnsafePtr,
+                            CheckedUnsafePtrCopyConstructed,
+                            CheckedUnsafePtrCopyAssigned,
+                            PointeeWithOneDanglingCheckedUnsafePtr,
+                            PointeeWithOneCopiedDanglingCheckedUnsafePtr,
+                            PointeeWithOneCopyAssignedDanglingCheckedUnsafePtr);
+
+using BothTypes = ::testing::Types<BasePointee, DerivedPointee>;
+INSTANTIATE_TYPED_TEST_SUITE_P(InstantiationOf, TypedCheckedUnsafePtrTest,
+                               BothTypes);
diff --git a/dom/quota/test/gtest/TestClientUsageArray.cpp b/dom/quota/test/gtest/TestClientUsageArray.cpp
new file mode 100644
index 0000000000..f5db984ccd
--- /dev/null
+++ b/dom/quota/test/gtest/TestClientUsageArray.cpp
@@ -0,0 +1,17 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ClientUsageArray.h"
+#include "gtest/gtest.h"
+
+using namespace mozilla::dom::quota;
+
+TEST(DOM_Quota_ClientUsageArray, Deserialize)
+{
+  ClientUsageArray clientUsages;
+  nsresult rv = clientUsages.Deserialize("I872215 C8404073805 L161709"_ns);
+  ASSERT_EQ(rv, NS_OK);
+}
diff --git a/dom/quota/test/gtest/TestEncryptedStream.cpp b/dom/quota/test/gtest/TestEncryptedStream.cpp
new file mode 100644
index 0000000000..b5e64f2cf1
--- /dev/null
+++ b/dom/quota/test/gtest/TestEncryptedStream.cpp
@@ -0,0 +1,786 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gtest/gtest.h"
+
+#include <algorithm>
+#include <cstdint>
+#include <cstdlib>
+#include <new>
+#include <numeric>
+#include <ostream>
+#include <string>
+#include <type_traits>
+#include <utility>
+#include <vector>
+#include "ErrorList.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/FixedBufferOutputStream.h"
+#include "mozilla/NotNull.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Scoped.h"
+#include "mozilla/Span.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/dom/SafeRefPtr.h"
+#include "mozilla/dom/quota/DecryptingInputStream_impl.h"
+#include "mozilla/dom/quota/DummyCipherStrategy.h"
+#include "mozilla/dom/quota/EncryptedBlock.h"
+#include "mozilla/dom/quota/EncryptingOutputStream_impl.h"
+#include "mozilla/dom/quota/NSSCipherStrategy.h"
+#include "mozilla/fallible.h"
+#include "nsCOMPtr.h"
+#include "nsError.h"
+#include "nsICloneableInputStream.h"
+#include "nsIInputStream.h"
+#include "nsIOutputStream.h"
+#include "nsISeekableStream.h"
+#include "nsISupports.h"
+#include "nsITellableStream.h"
+#include "nsStreamUtils.h"
+#include "nsString.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nscore.h"
+#include "nss.h"
+
+namespace mozilla::dom::quota {
+
+// Similar to ArrayBufferInputStream from netwerk/base/ArrayBufferInputStream.h,
+// but this is initialized from a Span on construction, rather than lazily from
+// a JS ArrayBuffer.
+class ArrayBufferInputStream : public nsIInputStream,
+                               public nsISeekableStream,
+                               public nsICloneableInputStream {
+ public:
+  explicit ArrayBufferInputStream(mozilla::Span<const uint8_t> aData);
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIINPUTSTREAM
+  NS_DECL_NSITELLABLESTREAM
+  NS_DECL_NSISEEKABLESTREAM
+  NS_DECL_NSICLONEABLEINPUTSTREAM
+
+ private:
+  virtual ~ArrayBufferInputStream() = default;
+
+  mozilla::UniquePtr<char[]> mArrayBuffer;
+  uint32_t mBufferLength;
+  uint32_t mPos;
+  bool mClosed;
+};
+
+NS_IMPL_ADDREF(ArrayBufferInputStream);
+NS_IMPL_RELEASE(ArrayBufferInputStream);
+
+NS_INTERFACE_MAP_BEGIN(ArrayBufferInputStream)
+  NS_INTERFACE_MAP_ENTRY(nsIInputStream)
+  NS_INTERFACE_MAP_ENTRY(nsISeekableStream)
+  NS_INTERFACE_MAP_ENTRY(nsICloneableInputStream)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIInputStream)
+NS_INTERFACE_MAP_END
+
+ArrayBufferInputStream::ArrayBufferInputStream(
+    mozilla::Span<const uint8_t> aData)
+    : mArrayBuffer(MakeUnique<char[]>(aData.Length())),
+      mBufferLength(aData.Length()),
+      mPos(0),
+      mClosed(false) {
+  std::copy(aData.cbegin(), aData.cend(), mArrayBuffer.get());
+}
+
+NS_IMETHODIMP
+ArrayBufferInputStream::Close() {
+  mClosed = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+ArrayBufferInputStream::Available(uint64_t* aCount) {
+  if (mClosed) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  if (mArrayBuffer) {
+    *aCount = mBufferLength ? mBufferLength - mPos : 0;
+  } else {
+    *aCount = 0;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+ArrayBufferInputStream::Read(char* aBuf, uint32_t aCount,
+                             uint32_t* aReadCount) {
+  return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount);
+}
+
+NS_IMETHODIMP
+ArrayBufferInputStream::ReadSegments(nsWriteSegmentFun writer, void* closure,
+                                     uint32_t aCount, uint32_t* result) {
+  MOZ_ASSERT(result, "null ptr");
+  MOZ_ASSERT(mBufferLength >= mPos, "bad stream state");
+
+  if (mClosed) {
+    return NS_BASE_STREAM_CLOSED;
+  }
+
+  MOZ_ASSERT(mArrayBuffer || (mPos == mBufferLength),
+             "stream inited incorrectly");
+
+  *result = 0;
+  while (mPos < mBufferLength) {
+    uint32_t remaining = mBufferLength - mPos;
+    MOZ_ASSERT(mArrayBuffer);
+
+    uint32_t count = std::min(aCount, remaining);
+    if (count == 0) {
+      break;
+    }
+
+    uint32_t written;
+    nsresult rv = writer(this, closure, &mArrayBuffer[0] + mPos, *result, count,
+                         &written);
+    if (NS_FAILED(rv)) {
+      // InputStreams do not propagate errors to caller.
+      return NS_OK;
+    }
+
+    MOZ_ASSERT(written <= count,
+               "writer should not write more than we asked it to write");
+    mPos += written;
+    *result += written;
+    aCount -= written;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+ArrayBufferInputStream::IsNonBlocking(bool* aNonBlocking) {
+  // Actually, the stream never blocks, but we lie about it because of the
+  // assumptions in DecryptingInputStream.
+  *aNonBlocking = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP ArrayBufferInputStream::Tell(int64_t* const aRetval) {
+  MOZ_ASSERT(aRetval);
+
+  *aRetval = mPos;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP ArrayBufferInputStream::Seek(const int32_t aWhence,
+                                           const int64_t aOffset) {
+  // XXX This is not safe. it's hard to use CheckedInt here, though. As long as
+  // the class is only used for testing purposes, that's probably fine.
+
+  int32_t newPos = mPos;
+  switch (aWhence) {
+    case NS_SEEK_SET:
+      newPos = aOffset;
+      break;
+    case NS_SEEK_CUR:
+      newPos += aOffset;
+      break;
+    case NS_SEEK_END:
+      newPos = mBufferLength;
+      newPos += aOffset;
+      break;
+    default:
+      return NS_ERROR_ILLEGAL_VALUE;
+  }
+  if (newPos < 0 || static_cast<uint32_t>(newPos) > mBufferLength) {
+    return NS_ERROR_ILLEGAL_VALUE;
+  }
+  mPos = newPos;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP ArrayBufferInputStream::SetEOF() {
+  // Truncating is not supported on a read-only stream.
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP ArrayBufferInputStream::GetCloneable(bool* aCloneable) {
+  *aCloneable = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP ArrayBufferInputStream::Clone(nsIInputStream** _retval) {
+  *_retval = MakeAndAddRef<ArrayBufferInputStream>(
+                 AsBytes(Span{mArrayBuffer.get(), mBufferLength}))
+                 .take();
+
+  return NS_OK;
+}
+}  // namespace mozilla::dom::quota
+
+namespace mozilla {
+MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLATE(ScopedNSSContext, NSSInitContext,
+                                          NSS_ShutdownContext);
+
+}  // namespace mozilla
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+class DOM_Quota_EncryptedStream : public ::testing::Test {
+ public:
+  static void SetUpTestCase() {
+    // Do this only once, do not tear it down per test case.
+    if (!sNssContext) {
+      sNssContext =
+          NSS_InitContext("", "", "", "", nullptr,
+                          NSS_INIT_READONLY | NSS_INIT_NOCERTDB |
+                              NSS_INIT_NOMODDB | NSS_INIT_FORCEOPEN |
+                              NSS_INIT_OPTIMIZESPACE | NSS_INIT_NOROOTINIT);
+    }
+  }
+
+  static void TearDownTestCase() { sNssContext = nullptr; }
+
+ private:
+  inline static ScopedNSSContext sNssContext = ScopedNSSContext{};
+};
+
+enum struct FlushMode { AfterEachChunk, Never };
+enum struct ChunkSize { SingleByte, Unaligned, DataSize };
+
+using PackedTestParams =
+    std::tuple<size_t, ChunkSize, ChunkSize, size_t, FlushMode>;
+
+static size_t EffectiveChunkSize(const ChunkSize aChunkSize,
+                                 const size_t aDataSize) {
+  switch (aChunkSize) {
+    case ChunkSize::SingleByte:
+      return 1;
+    case ChunkSize::Unaligned:
+      return 17;
+    case ChunkSize::DataSize:
+      return aDataSize;
+  }
+  MOZ_CRASH("Unknown ChunkSize");
+}
+
+struct TestParams {
+  MOZ_IMPLICIT constexpr TestParams(const PackedTestParams& aPackedParams)
+      : mDataSize(std::get<0>(aPackedParams)),
+        mWriteChunkSize(std::get<1>(aPackedParams)),
+        mReadChunkSize(std::get<2>(aPackedParams)),
+        mBlockSize(std::get<3>(aPackedParams)),
+        mFlushMode(std::get<4>(aPackedParams)) {}
+
+  constexpr size_t DataSize() const { return mDataSize; }
+
+  size_t EffectiveWriteChunkSize() const {
+    return EffectiveChunkSize(mWriteChunkSize, mDataSize);
+  }
+
+  size_t EffectiveReadChunkSize() const {
+    return EffectiveChunkSize(mReadChunkSize, mDataSize);
+  }
+
+  constexpr size_t BlockSize() const { return mBlockSize; }
+
+  constexpr enum FlushMode FlushMode() const { return mFlushMode; }
+
+ private:
+  size_t mDataSize;
+
+  ChunkSize mWriteChunkSize;
+  ChunkSize mReadChunkSize;
+
+  size_t mBlockSize;
+  enum FlushMode mFlushMode;
+};
+
+std::string TestParamToString(
+    const testing::TestParamInfo<PackedTestParams>& aTestParams) {
+  const TestParams& testParams = aTestParams.param;
+
+  static constexpr char kSeparator[] = "_";
+
+  std::stringstream ss;
+  ss << "data" << testParams.DataSize() << kSeparator << "writechunk"
+     << testParams.EffectiveWriteChunkSize() << kSeparator << "readchunk"
+     << testParams.EffectiveReadChunkSize() << kSeparator << "block"
+     << testParams.BlockSize() << kSeparator;
+  switch (testParams.FlushMode()) {
+    case FlushMode::Never:
+      ss << "FlushNever";
+      break;
+    case FlushMode::AfterEachChunk:
+      ss << "FlushAfterEachChunk";
+      break;
+  };
+  return ss.str();
+}
+
+class ParametrizedCryptTest
+    : public DOM_Quota_EncryptedStream,
+      public testing::WithParamInterface<PackedTestParams> {};
+
+static auto MakeTestData(const size_t aDataSize) {
+  auto data = nsTArray<uint8_t>();
+  data.SetLength(aDataSize);
+  std::iota(data.begin(), data.end(), 0);
+  return data;
+}
+
+template <typename CipherStrategy>
+static void WriteTestData(nsCOMPtr<nsIOutputStream>&& aBaseOutputStream,
+                          const Span<const uint8_t> aData,
+                          const size_t aWriteChunkSize, const size_t aBlockSize,
+                          const typename CipherStrategy::KeyType& aKey,
+                          const FlushMode aFlushMode) {
+  auto outStream = MakeSafeRefPtr<EncryptingOutputStream<CipherStrategy>>(
+      std::move(aBaseOutputStream), aBlockSize, aKey);
+
+  for (auto remaining = aData; !remaining.IsEmpty();) {
+    auto [currentChunk, newRemaining] =
+        remaining.SplitAt(std::min(aWriteChunkSize, remaining.Length()));
+    remaining = newRemaining;
+
+    uint32_t written;
+    EXPECT_EQ(NS_OK, outStream->Write(
+                         reinterpret_cast<const char*>(currentChunk.Elements()),
+                         currentChunk.Length(), &written));
+    EXPECT_EQ(currentChunk.Length(), written);
+
+    if (aFlushMode == FlushMode::AfterEachChunk) {
+      outStream->Flush();
+    }
+  }
+
+  // Close explicitly so we can check the result.
+  EXPECT_EQ(NS_OK, outStream->Close());
+}
+
+template <typename CipherStrategy>
+static void NoExtraChecks(DecryptingInputStream<CipherStrategy>& aInputStream,
+                          Span<const uint8_t> aExpectedData,
+                          Span<const uint8_t> aRemainder) {}
+
+template <typename CipherStrategy,
+          typename ExtraChecks = decltype(NoExtraChecks<CipherStrategy>)>
+static void ReadTestData(
+    DecryptingInputStream<CipherStrategy>& aDecryptingInputStream,
+    const Span<const uint8_t> aExpectedData, const size_t aReadChunkSize,
+    const ExtraChecks& aExtraChecks = NoExtraChecks<CipherStrategy>) {
+  auto readData = nsTArray<uint8_t>();
+  readData.SetLength(aReadChunkSize);
+  for (auto remainder = aExpectedData; !remainder.IsEmpty();) {
+    auto [currentExpected, newExpectedRemainder] =
+        remainder.SplitAt(std::min(aReadChunkSize, remainder.Length()));
+    remainder = newExpectedRemainder;
+
+    uint32_t read;
+    EXPECT_EQ(NS_OK, aDecryptingInputStream.Read(
+                         reinterpret_cast<char*>(readData.Elements()),
+                         currentExpected.Length(), &read));
+    EXPECT_EQ(currentExpected.Length(), read);
+    EXPECT_EQ(currentExpected,
+              Span{readData}.First(currentExpected.Length()).AsConst());
+
+    aExtraChecks(aDecryptingInputStream, aExpectedData, remainder);
+  }
+
+  // Expect EOF.
+  uint32_t read;
+  EXPECT_EQ(NS_OK, aDecryptingInputStream.Read(
+                       reinterpret_cast<char*>(readData.Elements()),
+                       readData.Length(), &read));
+  EXPECT_EQ(0u, read);
+}
+
+template <typename CipherStrategy,
+          typename ExtraChecks = decltype(NoExtraChecks<CipherStrategy>)>
+static auto ReadTestData(
+    MovingNotNull<nsCOMPtr<nsIInputStream>>&& aBaseInputStream,
+    const Span<const uint8_t> aExpectedData, const size_t aReadChunkSize,
+    const size_t aBlockSize, const typename CipherStrategy::KeyType& aKey,
+    const ExtraChecks& aExtraChecks = NoExtraChecks<CipherStrategy>) {
+  auto inStream = MakeSafeRefPtr<DecryptingInputStream<CipherStrategy>>(
+      std::move(aBaseInputStream), aBlockSize, aKey);
+
+  ReadTestData(*inStream, aExpectedData, aReadChunkSize, aExtraChecks);
+
+  return inStream;
+}
+
+// XXX Change to return the buffer instead.
+template <typename CipherStrategy,
+          typename ExtraChecks = decltype(NoExtraChecks<CipherStrategy>)>
+static RefPtr<FixedBufferOutputStream> DoRoundtripTest(
+    const size_t aDataSize, const size_t aWriteChunkSize,
+    const size_t aReadChunkSize, const size_t aBlockSize,
+    const typename CipherStrategy::KeyType& aKey, const FlushMode aFlushMode,
+    const ExtraChecks& aExtraChecks = NoExtraChecks<CipherStrategy>) {
+  // XXX Add deduction guide for RefPtr from already_AddRefed
+  const auto baseOutputStream = WrapNotNull(
+      RefPtr<FixedBufferOutputStream>{FixedBufferOutputStream::Create(2048)});
+
+  const auto data = MakeTestData(aDataSize);
+
+  WriteTestData<CipherStrategy>(
+      nsCOMPtr<nsIOutputStream>{baseOutputStream.get()}, Span{data},
+      aWriteChunkSize, aBlockSize, aKey, aFlushMode);
+
+  const auto baseInputStream =
+      MakeRefPtr<ArrayBufferInputStream>(baseOutputStream->WrittenData());
+
+  ReadTestData<CipherStrategy>(
+      WrapNotNull(nsCOMPtr<nsIInputStream>{baseInputStream}), Span{data},
+      aReadChunkSize, aBlockSize, aKey, aExtraChecks);
+
+  return baseOutputStream;
+}
+
+TEST_P(ParametrizedCryptTest, NSSCipherStrategy) {
+  using CipherStrategy = NSSCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  auto keyOrErr = CipherStrategy::GenerateKey();
+  ASSERT_FALSE(keyOrErr.isErr());
+
+  DoRoundtripTest<CipherStrategy>(
+      testParams.DataSize(), testParams.EffectiveWriteChunkSize(),
+      testParams.EffectiveReadChunkSize(), testParams.BlockSize(),
+      keyOrErr.unwrap(), testParams.FlushMode());
+}
+
+TEST_P(ParametrizedCryptTest, DummyCipherStrategy_CheckOutput) {
+  using CipherStrategy = DummyCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  const auto encryptedDataStream = DoRoundtripTest<CipherStrategy>(
+      testParams.DataSize(), testParams.EffectiveWriteChunkSize(),
+      testParams.EffectiveReadChunkSize(), testParams.BlockSize(),
+      CipherStrategy::KeyType{}, testParams.FlushMode());
+
+  if (HasFailure()) {
+    return;
+  }
+
+  const auto encryptedData = encryptedDataStream->WrittenData();
+  const auto encryptedDataSpan = AsBytes(Span(encryptedData));
+
+  const auto plainTestData = MakeTestData(testParams.DataSize());
+  auto encryptedBlock = EncryptedBlock<DummyCipherStrategy::BlockPrefixLength,
+                                       DummyCipherStrategy::BasicBlockSize>{
+      testParams.BlockSize(),
+  };
+  for (auto [encryptedRemainder, plainRemainder] =
+           std::pair(encryptedDataSpan, Span(plainTestData));
+       !encryptedRemainder.IsEmpty();) {
+    const auto [currentBlock, newEncryptedRemainder] =
+        encryptedRemainder.SplitAt(testParams.BlockSize());
+    encryptedRemainder = newEncryptedRemainder;
+
+    std::copy(currentBlock.cbegin(), currentBlock.cend(),
+              encryptedBlock.MutableWholeBlock().begin());
+
+    ASSERT_FALSE(plainRemainder.IsEmpty());
+    const auto [currentPlain, newPlainRemainder] =
+        plainRemainder.SplitAt(encryptedBlock.ActualPayloadLength());
+    plainRemainder = newPlainRemainder;
+
+    const auto pseudoIV = encryptedBlock.CipherPrefix();
+    const auto payload = encryptedBlock.Payload();
+
+    EXPECT_EQ(Span(DummyCipherStrategy::MakeBlockPrefix()), pseudoIV);
+
+    auto untransformedPayload = nsTArray<uint8_t>();
+    untransformedPayload.SetLength(testParams.BlockSize());
+    DummyCipherStrategy::DummyTransform(payload, untransformedPayload);
+
+    EXPECT_EQ(
+        currentPlain,
+        Span(untransformedPayload).AsConst().First(currentPlain.Length()));
+  }
+}
+
+TEST_P(ParametrizedCryptTest, DummyCipherStrategy_Tell) {
+  using CipherStrategy = DummyCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  DoRoundtripTest<CipherStrategy>(
+      testParams.DataSize(), testParams.EffectiveWriteChunkSize(),
+      testParams.EffectiveReadChunkSize(), testParams.BlockSize(),
+      CipherStrategy::KeyType{}, testParams.FlushMode(),
+      [](auto& inStream, Span<const uint8_t> expectedData,
+         Span<const uint8_t> remainder) {
+        // Check that Tell tells the right position.
+        int64_t pos;
+        EXPECT_EQ(NS_OK, inStream.Tell(&pos));
+        EXPECT_EQ(expectedData.Length() - remainder.Length(),
+                  static_cast<uint64_t>(pos));
+      });
+}
+
+TEST_P(ParametrizedCryptTest, DummyCipherStrategy_Available) {
+  using CipherStrategy = DummyCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  DoRoundtripTest<CipherStrategy>(
+      testParams.DataSize(), testParams.EffectiveWriteChunkSize(),
+      testParams.EffectiveReadChunkSize(), testParams.BlockSize(),
+      CipherStrategy::KeyType{}, testParams.FlushMode(),
+      [](auto& inStream, Span<const uint8_t> expectedData,
+         Span<const uint8_t> remainder) {
+        // Check that Available tells the right remainder.
+        uint64_t available;
+        EXPECT_EQ(NS_OK, inStream.Available(&available));
+        EXPECT_EQ(remainder.Length(), available);
+      });
+}
+
+TEST_P(ParametrizedCryptTest, DummyCipherStrategy_Clone) {
+  using CipherStrategy = DummyCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  // XXX Add deduction guide for RefPtr from already_AddRefed
+  const auto baseOutputStream = WrapNotNull(
+      RefPtr<FixedBufferOutputStream>{FixedBufferOutputStream::Create(2048)});
+
+  const auto data = MakeTestData(testParams.DataSize());
+
+  WriteTestData<CipherStrategy>(
+      nsCOMPtr<nsIOutputStream>{baseOutputStream.get()}, Span{data},
+      testParams.EffectiveWriteChunkSize(), testParams.BlockSize(),
+      CipherStrategy::KeyType{}, testParams.FlushMode());
+
+  const auto baseInputStream =
+      MakeRefPtr<ArrayBufferInputStream>(baseOutputStream->WrittenData());
+
+  const auto inStream = ReadTestData<CipherStrategy>(
+      WrapNotNull(nsCOMPtr<nsIInputStream>{baseInputStream}), Span{data},
+      testParams.EffectiveReadChunkSize(), testParams.BlockSize(),
+      CipherStrategy::KeyType{});
+
+  nsCOMPtr<nsIInputStream> clonedInputStream;
+  EXPECT_EQ(NS_OK, inStream->Clone(getter_AddRefs(clonedInputStream)));
+
+  ReadTestData(
+      static_cast<DecryptingInputStream<CipherStrategy>&>(*clonedInputStream),
+      Span{data}, testParams.EffectiveReadChunkSize());
+}
+
+// XXX This test is actually only parametrized on the block size.
+TEST_P(ParametrizedCryptTest, DummyCipherStrategy_IncompleteBlock) {
+  using CipherStrategy = DummyCipherStrategy;
+  const TestParams& testParams = GetParam();
+
+  // Provide half a block, content doesn't matter.
+  nsTArray<uint8_t> data;
+  data.SetLength(testParams.BlockSize() / 2);
+
+  const auto baseInputStream = MakeRefPtr<ArrayBufferInputStream>(data);
+
+  const auto inStream = MakeSafeRefPtr<DecryptingInputStream<CipherStrategy>>(
+      WrapNotNull(nsCOMPtr<nsIInputStream>{baseInputStream}),
+      testParams.BlockSize(), CipherStrategy::KeyType{});
+
+  nsTArray<uint8_t> readData;
+  readData.SetLength(testParams.BlockSize());
+  uint32_t read;
+  EXPECT_EQ(NS_ERROR_CORRUPTED_CONTENT,
+            inStream->Read(reinterpret_cast<char*>(readData.Elements()),
+                           readData.Length(), &read));
+}
+
+enum struct SeekOffset {
+  Zero,
+  MinusHalfDataSize,
+  PlusHalfDataSize,
+  PlusDataSize,
+  MinusDataSize
+};
+using SeekOp = std::pair<int32_t, SeekOffset>;
+
+using PackedSeekTestParams = std::tuple<size_t, size_t, std::vector<SeekOp>>;
+
+struct SeekTestParams {
+  size_t mDataSize;
+  size_t mBlockSize;
+  std::vector<SeekOp> mSeekOps;
+
+  MOZ_IMPLICIT SeekTestParams(const PackedSeekTestParams& aPackedParams)
+      : mDataSize(std::get<0>(aPackedParams)),
+        mBlockSize(std::get<1>(aPackedParams)),
+        mSeekOps(std::get<2>(aPackedParams)) {}
+};
+
+std::string SeekTestParamToString(
+    const testing::TestParamInfo<PackedSeekTestParams>& aTestParams) {
+  const SeekTestParams& testParams = aTestParams.param;
+
+  static constexpr char kSeparator[] = "_";
+
+  std::stringstream ss;
+  ss << "data" << testParams.mDataSize << kSeparator << "writechunk"
+     << testParams.mBlockSize << kSeparator;
+  for (const auto& seekOp : testParams.mSeekOps) {
+    switch (seekOp.first) {
+      case nsISeekableStream::NS_SEEK_SET:
+        ss << "Set";
+        break;
+      case nsISeekableStream::NS_SEEK_CUR:
+        ss << "Cur";
+        break;
+      case nsISeekableStream::NS_SEEK_END:
+        ss << "End";
+        break;
+    };
+    switch (seekOp.second) {
+      case SeekOffset::Zero:
+        ss << "Zero";
+        break;
+      case SeekOffset::MinusHalfDataSize:
+        ss << "MinusHalfDataSize";
+        break;
+      case SeekOffset::PlusHalfDataSize:
+        ss << "PlusHalfDataSize";
+        break;
+      case SeekOffset::MinusDataSize:
+        ss << "MinusDataSize";
+        break;
+      case SeekOffset::PlusDataSize:
+        ss << "PlusDataSize";
+        break;
+    };
+  }
+  return ss.str();
+}
+
+class ParametrizedSeekCryptTest
+    : public DOM_Quota_EncryptedStream,
+      public testing::WithParamInterface<PackedSeekTestParams> {};
+
+TEST_P(ParametrizedSeekCryptTest, DummyCipherStrategy_Seek) {
+  using CipherStrategy = DummyCipherStrategy;
+  const SeekTestParams& testParams = GetParam();
+
+  const auto baseOutputStream = WrapNotNull(
+      RefPtr<FixedBufferOutputStream>{FixedBufferOutputStream::Create(2048)});
+
+  const auto data = MakeTestData(testParams.mDataSize);
+
+  WriteTestData<CipherStrategy>(
+      nsCOMPtr<nsIOutputStream>{baseOutputStream.get()}, Span{data},
+      testParams.mDataSize, testParams.mBlockSize, CipherStrategy::KeyType{},
+      FlushMode::Never);
+
+  const auto baseInputStream =
+      MakeRefPtr<ArrayBufferInputStream>(baseOutputStream->WrittenData());
+
+  const auto inStream = MakeSafeRefPtr<DecryptingInputStream<CipherStrategy>>(
+      WrapNotNull(nsCOMPtr<nsIInputStream>{baseInputStream}),
+      testParams.mBlockSize, CipherStrategy::KeyType{});
+
+  uint32_t accumulatedOffset = 0;
+  for (const auto& seekOp : testParams.mSeekOps) {
+    const auto offset = [offsetKind = seekOp.second,
+                         dataSize = testParams.mDataSize]() -> int64_t {
+      switch (offsetKind) {
+        case SeekOffset::Zero:
+          return 0;
+        case SeekOffset::MinusHalfDataSize:
+          return -static_cast<int64_t>(dataSize) / 2;
+        case SeekOffset::PlusHalfDataSize:
+          return dataSize / 2;
+        case SeekOffset::MinusDataSize:
+          return -static_cast<int64_t>(dataSize);
+        case SeekOffset::PlusDataSize:
+          return dataSize;
+      }
+      MOZ_CRASH("Unknown SeekOffset");
+    }();
+    switch (seekOp.first) {
+      case nsISeekableStream::NS_SEEK_SET:
+        accumulatedOffset = offset;
+        break;
+      case nsISeekableStream::NS_SEEK_CUR:
+        accumulatedOffset += offset;
+        break;
+      case nsISeekableStream::NS_SEEK_END:
+        accumulatedOffset = testParams.mDataSize + offset;
+        break;
+    }
+    EXPECT_EQ(NS_OK, inStream->Seek(seekOp.first, offset));
+  }
+
+  {
+    int64_t actualOffset;
+    EXPECT_EQ(NS_OK, inStream->Tell(&actualOffset));
+
+    EXPECT_EQ(actualOffset, accumulatedOffset);
+  }
+
+  auto readData = nsTArray<uint8_t>();
+  readData.SetLength(data.Length());
+  uint32_t read;
+  EXPECT_EQ(NS_OK, inStream->Read(reinterpret_cast<char*>(readData.Elements()),
+                                  readData.Length(), &read));
+  // XXX Or should 'read' indicate the actual number of bytes read,
+  // including the encryption overhead?
+  EXPECT_EQ(testParams.mDataSize - accumulatedOffset, read);
+  EXPECT_EQ(Span{data}.SplitAt(accumulatedOffset).second,
+            Span{readData}.First(read).AsConst());
+}
+
+INSTANTIATE_TEST_SUITE_P(
+    DOM_Quota_EncryptedStream_Parametrized, ParametrizedCryptTest,
+    testing::Combine(
+        /* dataSize */ testing::Values(0u, 16u, 256u, 512u, 513u),
+        /* writeChunkSize */
+        testing::Values(ChunkSize::SingleByte, ChunkSize::Unaligned,
+                        ChunkSize::DataSize),
+        /* readChunkSize */
+        testing::Values(ChunkSize::SingleByte, ChunkSize::Unaligned,
+                        ChunkSize::DataSize),
+        /* blockSize */ testing::Values(256u, 1024u /*, 8192u*/),
+        /* flushMode */
+        testing::Values(FlushMode::Never, FlushMode::AfterEachChunk)),
+    TestParamToString);
+
+INSTANTIATE_TEST_SUITE_P(
+    DOM_IndexedDB_EncryptedStream_ParametrizedSeek, ParametrizedSeekCryptTest,
+    testing::Combine(
+        /* dataSize */ testing::Values(0u, 16u, 256u, 512u, 513u),
+        /* blockSize */ testing::Values(256u, 1024u /*, 8192u*/),
+        /* seekOperations */
+        testing::Values(/* NS_SEEK_SET only, single ops */
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_SET,
+                                             SeekOffset::PlusDataSize}},
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_SET,
+                                             SeekOffset::PlusHalfDataSize}},
+                        /* NS_SEEK_SET only, multiple ops */
+                        std::vector<SeekOp>{
+                            {nsISeekableStream::NS_SEEK_SET,
+                             SeekOffset::PlusHalfDataSize},
+                            {nsISeekableStream::NS_SEEK_SET, SeekOffset::Zero}},
+                        /* NS_SEEK_CUR only, single ops */
+                        std::vector<SeekOp>{
+                            {nsISeekableStream::NS_SEEK_CUR, SeekOffset::Zero}},
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_CUR,
+                                             SeekOffset::PlusDataSize}},
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_CUR,
+                                             SeekOffset::PlusHalfDataSize}},
+                        /* NS_SEEK_END only, single ops */
+                        std::vector<SeekOp>{
+                            {nsISeekableStream::NS_SEEK_END, SeekOffset::Zero}},
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_END,
+                                             SeekOffset::MinusDataSize}},
+                        std::vector<SeekOp>{{nsISeekableStream::NS_SEEK_END,
+                                             SeekOffset::MinusHalfDataSize}})),
+    SeekTestParamToString);
diff --git a/dom/quota/test/gtest/TestFileOutputStream.cpp b/dom/quota/test/gtest/TestFileOutputStream.cpp
new file mode 100644
index 0000000000..b62f15363e
--- /dev/null
+++ b/dom/quota/test/gtest/TestFileOutputStream.cpp
@@ -0,0 +1,182 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/Client.h"
+#include "mozilla/dom/quota/CommonMetadata.h"
+#include "mozilla/dom/quota/FileStreams.h"
+#include "mozilla/dom/quota/QuotaManager.h"
+#include "mozilla/gtest/MozAssertions.h"
+#include "nsIPrefBranch.h"
+#include "nsIPrefService.h"
+#include "QuotaManagerDependencyFixture.h"
+
+namespace mozilla::dom::quota::test {
+
+class TestFileOutputStream : public QuotaManagerDependencyFixture {
+ public:
+  static void SetUpTestCase() {
+    ASSERT_NO_FATAL_FAILURE(InitializeFixture());
+
+    nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
+
+    prefs->SetIntPref("dom.quotaManager.temporaryStorage.fixedLimit",
+                      mQuotaLimit);
+  }
+
+  static void TearDownTestCase() {
+    nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
+
+    prefs->ClearUserPref("dom.quotaManager.temporaryStorage.fixedLimit");
+
+    ASSERT_NO_FATAL_FAILURE(ShutdownFixture());
+  }
+
+  static const int32_t mQuotaLimit = 8192;
+};
+
+TEST_F(TestFileOutputStream, extendFileStreamWithSetEOF) {
+  auto ioTask = []() {
+    quota::QuotaManager* quotaManager = quota::QuotaManager::Get();
+
+    auto originMetadata =
+        quota::OriginMetadata{""_ns, "example.com"_ns, "http://example.com"_ns,
+                              quota::PERSISTENCE_TYPE_DEFAULT};
+
+    {
+      ASSERT_NS_SUCCEEDED(quotaManager->EnsureStorageIsInitialized());
+
+      ASSERT_NS_SUCCEEDED(quotaManager->EnsureTemporaryStorageIsInitialized());
+
+      auto res = quotaManager->EnsureTemporaryOriginIsInitialized(
+          quota::PERSISTENCE_TYPE_DEFAULT, originMetadata);
+      ASSERT_TRUE(res.isOk());
+    }
+
+    const int64_t groupLimit =
+        static_cast<int64_t>(quotaManager->GetGroupLimit());
+    ASSERT_TRUE(mQuotaLimit * 1024LL == groupLimit);
+
+    // We don't use the tested stream itself to check the file size as it
+    // may report values which have not been written to disk.
+    RefPtr<quota::FileOutputStream> check = MakeRefPtr<quota::FileOutputStream>(
+        quota::PERSISTENCE_TYPE_DEFAULT, originMetadata,
+        quota::Client::Type::SDB);
+
+    RefPtr<quota::FileOutputStream> stream =
+        MakeRefPtr<quota::FileOutputStream>(quota::PERSISTENCE_TYPE_DEFAULT,
+                                            originMetadata,
+                                            quota::Client::Type::SDB);
+
+    {
+      auto testPathRes = quotaManager->GetDirectoryForOrigin(
+          quota::PERSISTENCE_TYPE_DEFAULT, originMetadata.mOrigin);
+
+      ASSERT_TRUE(testPathRes.isOk());
+
+      nsCOMPtr<nsIFile> testPath = testPathRes.unwrap();
+
+      ASSERT_NS_SUCCEEDED(testPath->AppendRelativePath(u"sdb"_ns));
+
+      ASSERT_NS_SUCCEEDED(
+          testPath->AppendRelativePath(u"tTestFileOutputStream.txt"_ns));
+
+      bool exists = true;
+      ASSERT_NS_SUCCEEDED(testPath->Exists(&exists));
+
+      if (exists) {
+        ASSERT_NS_SUCCEEDED(testPath->Remove(/* recursive */ false));
+      }
+
+      ASSERT_NS_SUCCEEDED(testPath->Exists(&exists));
+      ASSERT_FALSE(exists);
+
+      ASSERT_NS_SUCCEEDED(testPath->Create(nsIFile::NORMAL_FILE_TYPE, 0666));
+
+      ASSERT_NS_SUCCEEDED(testPath->Exists(&exists));
+      ASSERT_TRUE(exists);
+
+      nsCOMPtr<nsIFile> checkPath;
+      ASSERT_NS_SUCCEEDED(testPath->Clone(getter_AddRefs(checkPath)));
+
+      const int32_t IOFlags = -1;
+      const int32_t perm = -1;
+      const int32_t behaviorFlags = 0;
+      ASSERT_NS_SUCCEEDED(stream->Init(testPath, IOFlags, perm, behaviorFlags));
+
+      ASSERT_NS_SUCCEEDED(check->Init(testPath, IOFlags, perm, behaviorFlags));
+    }
+
+    // Check that we start with an empty file
+    int64_t avail = 42;
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(0 == avail);
+
+    // Enlarge the file
+    const int64_t toSize = groupLimit;
+    ASSERT_NS_SUCCEEDED(stream->Seek(nsISeekableStream::NS_SEEK_SET, toSize));
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(0 == avail);
+
+    ASSERT_NS_SUCCEEDED(stream->SetEOF());
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toSize == avail);
+
+    // Try to enlarge the file past the limit
+    const int64_t overGroupLimit = groupLimit + 1;
+
+    // Seeking is allowed
+    ASSERT_NS_SUCCEEDED(
+        stream->Seek(nsISeekableStream::NS_SEEK_SET, overGroupLimit));
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toSize == avail);
+
+    // Setting file size to exceed quota should yield no device space error
+    ASSERT_TRUE(NS_ERROR_FILE_NO_DEVICE_SPACE == stream->SetEOF());
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toSize == avail);
+
+    // Shrink the file
+    const int64_t toHalfSize = toSize / 2;
+    ASSERT_NS_SUCCEEDED(
+        stream->Seek(nsISeekableStream::NS_SEEK_SET, toHalfSize));
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toSize == avail);
+
+    ASSERT_NS_SUCCEEDED(stream->SetEOF());
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toHalfSize == avail);
+
+    // Shrink the file back to nothing
+    ASSERT_NS_SUCCEEDED(stream->Seek(nsISeekableStream::NS_SEEK_SET, 0));
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(toHalfSize == avail);
+
+    ASSERT_NS_SUCCEEDED(stream->SetEOF());
+
+    ASSERT_NS_SUCCEEDED(check->GetSize(&avail));
+
+    ASSERT_TRUE(0 == avail);
+  };
+
+  PerformOnIOThread(std::move(ioTask));
+}
+
+}  // namespace mozilla::dom::quota::test
diff --git a/dom/quota/test/gtest/TestFlatten.cpp b/dom/quota/test/gtest/TestFlatten.cpp
new file mode 100644
index 0000000000..5ca7675887
--- /dev/null
+++ b/dom/quota/test/gtest/TestFlatten.cpp
@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Flatten.h"
+
+#include "gtest/gtest.h"
+
+#include "mozilla/Unused.h"
+#include "nsTArray.h"
+
+namespace mozilla::dom::quota {
+
+#ifdef __clang__
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wunreachable-code-loop-increment"
+#endif
+TEST(Flatten, FlatEmpty)
+{
+  for (const auto& item : Flatten<int>(nsTArray<int>{})) {
+    Unused << item;
+    FAIL();
+  }
+}
+
+TEST(Flatten, NestedOuterEmpty)
+{
+  for (const auto& item : Flatten<int>(nsTArray<CopyableTArray<int>>{})) {
+    Unused << item;
+    FAIL();
+  }
+}
+
+TEST(Flatten, NestedInnerEmpty)
+{
+  for (const auto& item :
+       Flatten<int>(nsTArray<CopyableTArray<int>>{CopyableTArray<int>{}})) {
+    Unused << item;
+    FAIL();
+  }
+}
+#ifdef __clang__
+#  pragma clang diagnostic pop
+#endif
+
+TEST(Flatten, NestedInnerSingular)
+{
+  nsTArray<int> flattened;
+  for (const auto& item :
+       Flatten<int>(nsTArray<CopyableTArray<int>>{CopyableTArray<int>{1}})) {
+    flattened.AppendElement(item);
+  }
+
+  EXPECT_EQ(nsTArray{1}, flattened);
+}
+
+TEST(Flatten, NestedInnerSingulars)
+{
+  nsTArray<int> flattened;
+  for (const auto& item : Flatten<int>(nsTArray<CopyableTArray<int>>{
+           CopyableTArray<int>{1}, CopyableTArray<int>{2}})) {
+    flattened.AppendElement(item);
+  }
+
+  EXPECT_EQ((nsTArray<int>{{1, 2}}), flattened);
+}
+
+TEST(Flatten, NestedInnerNonSingulars)
+{
+  nsTArray<int> flattened;
+  for (const auto& item : Flatten<int>(nsTArray<CopyableTArray<int>>{
+           CopyableTArray<int>{1, 2}, CopyableTArray<int>{3, 4}})) {
+    flattened.AppendElement(item);
+  }
+
+  EXPECT_EQ((nsTArray<int>{{1, 2, 3, 4}}), flattened);
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/test/gtest/TestForwardDecls.cpp b/dom/quota/test/gtest/TestForwardDecls.cpp
new file mode 100644
index 0000000000..223f83af03
--- /dev/null
+++ b/dom/quota/test/gtest/TestForwardDecls.cpp
@@ -0,0 +1,12 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <type_traits>
+#include "mozilla/dom/quota/ForwardDecls.h"
+
+using namespace mozilla;
+
+static_assert(std::is_same_v<OkOrErr, Result<Ok, QMResult>>);
diff --git a/dom/quota/test/gtest/TestPersistenceType.cpp b/dom/quota/test/gtest/TestPersistenceType.cpp
new file mode 100644
index 0000000000..c4f1e5d581
--- /dev/null
+++ b/dom/quota/test/gtest/TestPersistenceType.cpp
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/PersistenceType.h"
+
+#include "gtest/gtest.h"
+
+#include "nsDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
+#include "nsIFile.h"
+
+namespace mozilla::dom::quota {
+
+TEST(PersistenceType, FromFile)
+{
+  nsCOMPtr<nsIFile> base;
+  nsresult rv = NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(base));
+  EXPECT_EQ(rv, NS_OK);
+
+  const auto testPersistenceType = [&base](const nsLiteralString& aString,
+                                           const Maybe<PersistenceType> aType) {
+    nsCOMPtr<nsIFile> file;
+
+    nsresult rv = base->Clone(getter_AddRefs(file));
+    EXPECT_EQ(rv, NS_OK);
+
+    rv = file->Append(aString);
+    EXPECT_EQ(rv, NS_OK);
+
+    auto maybePersistenceType = PersistenceTypeFromFile(*file, fallible);
+    EXPECT_EQ(maybePersistenceType, aType);
+  };
+
+  testPersistenceType(u"permanent"_ns, Some(PERSISTENCE_TYPE_PERSISTENT));
+  testPersistenceType(u"temporary"_ns, Some(PERSISTENCE_TYPE_TEMPORARY));
+  testPersistenceType(u"default"_ns, Some(PERSISTENCE_TYPE_DEFAULT));
+  testPersistenceType(u"persistent"_ns, Nothing());
+  testPersistenceType(u"foobar"_ns, Nothing());
+}
+
+}  // namespace mozilla::dom::quota
diff --git a/dom/quota/test/gtest/TestQMResult.cpp b/dom/quota/test/gtest/TestQMResult.cpp
new file mode 100644
index 0000000000..94cbec7364
--- /dev/null
+++ b/dom/quota/test/gtest/TestQMResult.cpp
@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Common.h"
+#include "gtest/gtest.h"
+#include "mozilla/dom/QMResult.h"
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+class DOM_Quota_QMResult : public DOM_Quota_Test {};
+
+#ifdef QM_ERROR_STACKS_ENABLED
+TEST_F(DOM_Quota_QMResult, Construct_Default) {
+  QMResult res;
+
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(res.StackId(), ExpectedStackId());
+  ASSERT_EQ(res.FrameId(), 1u);
+  ASSERT_EQ(res.NSResult(), NS_OK);
+}
+#endif
+
+TEST_F(DOM_Quota_QMResult, Construct_FromNSResult) {
+  QMResult res(NS_ERROR_FAILURE);
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(res.StackId(), ExpectedStackId());
+  ASSERT_EQ(res.FrameId(), 1u);
+  ASSERT_EQ(res.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(res, NS_ERROR_FAILURE);
+#endif
+}
+
+#ifdef QM_ERROR_STACKS_ENABLED
+TEST_F(DOM_Quota_QMResult, Propagate) {
+  QMResult res1(NS_ERROR_FAILURE);
+
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(res1.StackId(), ExpectedStackId());
+  ASSERT_EQ(res1.FrameId(), 1u);
+  ASSERT_EQ(res1.NSResult(), NS_ERROR_FAILURE);
+
+  QMResult res2 = res1.Propagate();
+
+  ASSERT_EQ(res2.StackId(), ExpectedStackId());
+  ASSERT_EQ(res2.FrameId(), 2u);
+  ASSERT_EQ(res2.NSResult(), NS_ERROR_FAILURE);
+}
+#endif
+
+TEST_F(DOM_Quota_QMResult, ToQMResult) {
+  auto res = ToQMResult(NS_ERROR_FAILURE);
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(res.StackId(), ExpectedStackId());
+  ASSERT_EQ(res.FrameId(), 1u);
+  ASSERT_EQ(res.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(res, NS_ERROR_FAILURE);
+#endif
+}
diff --git a/dom/quota/test/gtest/TestQuotaCommon.cpp b/dom/quota/test/gtest/TestQuotaCommon.cpp
new file mode 100644
index 0000000000..c1a047a533
--- /dev/null
+++ b/dom/quota/test/gtest/TestQuotaCommon.cpp
@@ -0,0 +1,2171 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/QuotaCommon.h"
+
+#include "gtest/gtest.h"
+
+#include <algorithm>
+#include <array>
+#include <cstddef>
+#include <cstdint>
+#include <map>
+#include <new>
+#include <ostream>
+#include <type_traits>
+#include <utility>
+#include <vector>
+#include "ErrorList.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/ResultVariant.h"
+#include "mozilla/Unused.h"
+#include "mozilla/fallible.h"
+#include "mozilla/dom/quota/QuotaTestParent.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+#include "nsCOMPtr.h"
+#include "nsLiteralString.h"
+#include "nsString.h"
+#include "nsStringFwd.h"
+#include "nsTLiteralString.h"
+
+class nsISupports;
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+mozilla::ipc::IPCResult QuotaTestParent::RecvTry_Success_CustomErr_QmIpcFail(
+    bool* aTryDidNotReturn) {
+  QM_TRY(MOZ_TO_RESULT(NS_OK), QM_IPC_FAIL(this));
+
+  *aTryDidNotReturn = true;
+
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult QuotaTestParent::RecvTry_Success_CustomErr_IpcFail(
+    bool* aTryDidNotReturn) {
+  QM_TRY(MOZ_TO_RESULT(NS_OK), IPC_FAIL(this, "Custom why"));
+
+  *aTryDidNotReturn = true;
+
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult
+QuotaTestParent::RecvTryInspect_Success_CustomErr_QmIpcFail(
+    bool* aTryDidNotReturn) {
+  QM_TRY_INSPECT(const auto& x, (mozilla::Result<int32_t, nsresult>{42}),
+                 QM_IPC_FAIL(this));
+  Unused << x;
+
+  *aTryDidNotReturn = true;
+
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult
+QuotaTestParent::RecvTryInspect_Success_CustomErr_IpcFail(
+    bool* aTryDidNotReturn) {
+  QM_TRY_INSPECT(const auto& x, (mozilla::Result<int32_t, nsresult>{42}),
+                 IPC_FAIL(this, "Custom why"));
+  Unused << x;
+
+  *aTryDidNotReturn = true;
+
+  return IPC_OK();
+}
+
+#ifdef __clang__
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+
+TEST(QuotaCommon_Try, Success)
+{
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, Success_CustomErr_QmIpcFail)
+{
+  auto foo = MakeRefPtr<QuotaTestParent>();
+
+  bool tryDidNotReturn = false;
+
+  auto res = foo->RecvTry_Success_CustomErr_QmIpcFail(&tryDidNotReturn);
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_TRUE(res);
+}
+
+TEST(QuotaCommon_Try, Success_CustomErr_IpcFail)
+{
+  auto foo = MakeRefPtr<QuotaTestParent>();
+
+  bool tryDidNotReturn = false;
+
+  auto res = foo->RecvTry_Success_CustomErr_IpcFail(&tryDidNotReturn);
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_TRUE(res);
+}
+
+#ifdef DEBUG
+TEST(QuotaCommon_Try, Success_CustomErr_AssertUnreachable)
+{
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_OK), QM_ASSERT_UNREACHABLE);
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, Success_NoErr_AssertUnreachable)
+{
+  bool tryDidNotReturn = false;
+
+  [&tryDidNotReturn]() -> void {
+    QM_TRY(MOZ_TO_RESULT(NS_OK), QM_ASSERT_UNREACHABLE_VOID);
+
+    tryDidNotReturn = true;
+  }();
+
+  EXPECT_TRUE(tryDidNotReturn);
+}
+#else
+#  if defined(QM_ASSERT_UNREACHABLE) || defined(QM_ASSERT_UNREACHABLE_VOID)
+#error QM_ASSERT_UNREACHABLE and QM_ASSERT_UNREACHABLE_VOID should not be defined.
+#  endif
+#endif
+
+#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
+TEST(QuotaCommon_Try, Success_CustomErr_DiagnosticAssertUnreachable)
+{
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_OK), QM_DIAGNOSTIC_ASSERT_UNREACHABLE);
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, Success_NoErr_DiagnosticAssertUnreachable)
+{
+  bool tryDidNotReturn = false;
+
+  [&tryDidNotReturn]() -> void {
+    QM_TRY(MOZ_TO_RESULT(NS_OK), QM_DIAGNOSTIC_ASSERT_UNREACHABLE_VOID);
+
+    tryDidNotReturn = true;
+  }();
+
+  EXPECT_TRUE(tryDidNotReturn);
+}
+#else
+#  if defined(QM_DIAGNOSTIC_ASSERT_UNREACHABLE) || \
+      defined(QM_DIAGNOSTIC_ASSERT_UNREACHABLE_VOID)
+#error QM_DIAGNOSTIC_ASSERT_UNREACHABLE and QM_DIAGNOSTIC_ASSERT_UNREACHABLE_VOID should not be defined.
+#  endif
+#endif
+
+TEST(QuotaCommon_Try, Success_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                                 \
+  {                                                                  \
+    bool tryDidNotReturn = false;                                    \
+                                                                     \
+    nsresult rv = [&tryDidNotReturn]() -> nsresult {                 \
+      QM_TRY(MOZ_TO_RESULT(NS_OK), [](__VA_ARGS__) { return aRv; }); \
+                                                                     \
+      tryDidNotReturn = true;                                        \
+                                                                     \
+      return NS_OK;                                                  \
+    }();                                                             \
+                                                                     \
+    EXPECT_TRUE(tryDidNotReturn);                                    \
+    EXPECT_EQ(rv, NS_OK);                                            \
+  }
+
+  SUBTEST(const char*, nsresult aRv);
+  SUBTEST(nsresult aRv);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_Try, Success_WithCleanup)
+{
+  bool tryCleanupRan = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryCleanupRan, &tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_OK), QM_PROPAGATE,
+           [&tryCleanupRan](const auto&) { tryCleanupRan = true; });
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryCleanupRan);
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, Failure_PropagateErr)
+{
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Try, Failure_CustomErr)
+{
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE), NS_ERROR_UNEXPECTED);
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_Try, Failure_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                           \
+  {                                                            \
+    bool tryDidNotReturn = false;                              \
+                                                               \
+    nsresult rv = [&tryDidNotReturn]() -> nsresult {           \
+      QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE),                  \
+             [](__VA_ARGS__) { return NS_ERROR_UNEXPECTED; }); \
+                                                               \
+      tryDidNotReturn = true;                                  \
+                                                               \
+      return NS_OK;                                            \
+    }();                                                       \
+                                                               \
+    EXPECT_FALSE(tryDidNotReturn);                             \
+    EXPECT_EQ(rv, NS_ERROR_UNEXPECTED);                        \
+  }
+
+  SUBTEST(const char* aFunc, nsresult);
+  SUBTEST(nsresult rv);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_Try, Failure_NoErr)
+{
+  bool tryDidNotReturn = false;
+
+  [&tryDidNotReturn]() -> void {
+    QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE), QM_VOID);
+
+    tryDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryDidNotReturn);
+}
+
+TEST(QuotaCommon_Try, Failure_WithCleanup)
+{
+  bool tryCleanupRan = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&tryCleanupRan, &tryDidNotReturn]() -> nsresult {
+    QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE), QM_PROPAGATE,
+           [&tryCleanupRan](const auto& result) {
+             EXPECT_EQ(result, NS_ERROR_FAILURE);
+
+             tryCleanupRan = true;
+           });
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryCleanupRan);
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Try, Failure_WithCleanup_UnwrapErr)
+{
+  bool tryCleanupRan = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv;
+
+  [&tryCleanupRan, &tryDidNotReturn](nsresult& aRv) -> void {
+    QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE), QM_VOID,
+           ([&tryCleanupRan, &aRv](auto& result) {
+             EXPECT_EQ(result, NS_ERROR_FAILURE);
+
+             aRv = result;
+
+             tryCleanupRan = true;
+           }));
+
+    tryDidNotReturn = true;
+
+    aRv = NS_OK;
+  }(rv);
+
+  EXPECT_TRUE(tryCleanupRan);
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Try, SameLine)
+{
+  // clang-format off
+  QM_TRY(MOZ_TO_RESULT(NS_OK), QM_VOID); QM_TRY(MOZ_TO_RESULT(NS_OK), QM_VOID);
+  // clang-format on
+}
+
+TEST(QuotaCommon_Try, NestingMadness_Success)
+{
+  bool nestedTryDidNotReturn = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&nestedTryDidNotReturn, &tryDidNotReturn]() -> nsresult {
+    QM_TRY(([&nestedTryDidNotReturn]() -> Result<Ok, nsresult> {
+      QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+      nestedTryDidNotReturn = true;
+
+      return Ok();
+    }()));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTryDidNotReturn);
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, NestingMadness_Failure)
+{
+  bool nestedTryDidNotReturn = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&nestedTryDidNotReturn, &tryDidNotReturn]() -> nsresult {
+    QM_TRY(([&nestedTryDidNotReturn]() -> Result<Ok, nsresult> {
+      QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE));
+
+      nestedTryDidNotReturn = true;
+
+      return Ok();
+    }()));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(nestedTryDidNotReturn);
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Try, NestingMadness_Multiple_Success)
+{
+  bool nestedTry1DidNotReturn = false;
+  bool nestedTry2DidNotReturn = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&nestedTry1DidNotReturn, &nestedTry2DidNotReturn,
+                 &tryDidNotReturn]() -> nsresult {
+    QM_TRY(([&nestedTry1DidNotReturn,
+             &nestedTry2DidNotReturn]() -> Result<Ok, nsresult> {
+      QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+      nestedTry1DidNotReturn = true;
+
+      QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+      nestedTry2DidNotReturn = true;
+
+      return Ok();
+    }()));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTry1DidNotReturn);
+  EXPECT_TRUE(nestedTry2DidNotReturn);
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_Try, NestingMadness_Multiple_Failure1)
+{
+  bool nestedTry1DidNotReturn = false;
+  bool nestedTry2DidNotReturn = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&nestedTry1DidNotReturn, &nestedTry2DidNotReturn,
+                 &tryDidNotReturn]() -> nsresult {
+    QM_TRY(([&nestedTry1DidNotReturn,
+             &nestedTry2DidNotReturn]() -> Result<Ok, nsresult> {
+      QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE));
+
+      nestedTry1DidNotReturn = true;
+
+      QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+      nestedTry2DidNotReturn = true;
+
+      return Ok();
+    }()));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(nestedTry1DidNotReturn);
+  EXPECT_FALSE(nestedTry2DidNotReturn);
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Try, NestingMadness_Multiple_Failure2)
+{
+  bool nestedTry1DidNotReturn = false;
+  bool nestedTry2DidNotReturn = false;
+  bool tryDidNotReturn = false;
+
+  nsresult rv = [&nestedTry1DidNotReturn, &nestedTry2DidNotReturn,
+                 &tryDidNotReturn]() -> nsresult {
+    QM_TRY(([&nestedTry1DidNotReturn,
+             &nestedTry2DidNotReturn]() -> Result<Ok, nsresult> {
+      QM_TRY(MOZ_TO_RESULT(NS_OK));
+
+      nestedTry1DidNotReturn = true;
+
+      QM_TRY(MOZ_TO_RESULT(NS_ERROR_FAILURE));
+
+      nestedTry2DidNotReturn = true;
+
+      return Ok();
+    }()));
+
+    tryDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTry1DidNotReturn);
+  EXPECT_FALSE(nestedTry2DidNotReturn);
+  EXPECT_FALSE(tryDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, Success)
+{
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}));
+    EXPECT_EQ(x, 42);
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_TryInspect, Success_CustomErr_QmIpcFail)
+{
+  auto foo = MakeRefPtr<QuotaTestParent>();
+
+  bool tryDidNotReturn = false;
+
+  auto res = foo->RecvTryInspect_Success_CustomErr_QmIpcFail(&tryDidNotReturn);
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_TRUE(res);
+}
+
+TEST(QuotaCommon_TryInspect, Success_CustomErr_IpcFail)
+{
+  auto foo = MakeRefPtr<QuotaTestParent>();
+
+  bool tryDidNotReturn = false;
+
+  auto res = foo->RecvTryInspect_Success_CustomErr_IpcFail(&tryDidNotReturn);
+
+  EXPECT_TRUE(tryDidNotReturn);
+  EXPECT_TRUE(res);
+}
+
+#ifdef DEBUG
+TEST(QuotaCommon_TryInspect, Success_CustomErr_AssertUnreachable)
+{
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}),
+                   QM_ASSERT_UNREACHABLE);
+    EXPECT_EQ(x, 42);
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_TryInspect, Success_NoErr_AssertUnreachable)
+{
+  bool tryInspectDidNotReturn = false;
+
+  [&tryInspectDidNotReturn]() -> void {
+    QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}),
+                   QM_ASSERT_UNREACHABLE_VOID);
+    EXPECT_EQ(x, 42);
+
+    tryInspectDidNotReturn = true;
+  }();
+
+  EXPECT_TRUE(tryInspectDidNotReturn);
+}
+#endif
+
+TEST(QuotaCommon_TryInspect, Success_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                                 \
+  {                                                                  \
+    bool tryInspectDidNotReturn = false;                             \
+                                                                     \
+    nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {          \
+      QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}), \
+                     [](__VA_ARGS__) { return aRv; });               \
+      EXPECT_EQ(x, 42);                                              \
+                                                                     \
+      tryInspectDidNotReturn = true;                                 \
+                                                                     \
+      return NS_OK;                                                  \
+    }();                                                             \
+                                                                     \
+    EXPECT_TRUE(tryInspectDidNotReturn);                             \
+    EXPECT_EQ(rv, NS_OK);                                            \
+  }
+
+  SUBTEST(const char*, nsresult aRv);
+  SUBTEST(nsresult aRv);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_TryInspect, Success_WithCleanup)
+{
+  bool tryInspectCleanupRan = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectCleanupRan, &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& x, (Result<int32_t, nsresult>{42}), QM_PROPAGATE,
+        [&tryInspectCleanupRan](const auto&) { tryInspectCleanupRan = true; });
+    EXPECT_EQ(x, 42);
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryInspectCleanupRan);
+  EXPECT_TRUE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_TryInspect, Failure_PropagateErr)
+{
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(const auto& x,
+                   (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, Failure_CustomErr)
+{
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(const auto& x,
+                   (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}),
+                   NS_ERROR_UNEXPECTED);
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_TryInspect, Failure_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                                     \
+  {                                                                      \
+    bool tryInspectDidNotReturn = false;                                 \
+                                                                         \
+    nsresult rv = [&tryInspectDidNotReturn]() -> nsresult {              \
+      QM_TRY_INSPECT(const auto& x,                                      \
+                     (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}), \
+                     [](__VA_ARGS__) { return NS_ERROR_UNEXPECTED; });   \
+      Unused << x;                                                       \
+                                                                         \
+      tryInspectDidNotReturn = true;                                     \
+                                                                         \
+      return NS_OK;                                                      \
+    }();                                                                 \
+                                                                         \
+    EXPECT_FALSE(tryInspectDidNotReturn);                                \
+    EXPECT_EQ(rv, NS_ERROR_UNEXPECTED);                                  \
+  }
+
+  SUBTEST(const char*, nsresult);
+  SUBTEST(nsresult);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_TryInspect, Failure_NoErr)
+{
+  bool tryInspectDidNotReturn = false;
+
+  [&tryInspectDidNotReturn]() -> void {
+    QM_TRY_INSPECT(const auto& x,
+                   (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}), QM_VOID);
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryInspectDidNotReturn);
+}
+
+TEST(QuotaCommon_TryInspect, Failure_WithCleanup)
+{
+  bool tryInspectCleanupRan = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&tryInspectCleanupRan, &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(const auto& x,
+                   (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}),
+                   QM_PROPAGATE, [&tryInspectCleanupRan](const auto& result) {
+                     EXPECT_EQ(result, NS_ERROR_FAILURE);
+
+                     tryInspectCleanupRan = true;
+                   });
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(tryInspectCleanupRan);
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, Failure_WithCleanup_UnwrapErr)
+{
+  bool tryInspectCleanupRan = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv;
+
+  [&tryInspectCleanupRan, &tryInspectDidNotReturn](nsresult& aRv) -> void {
+    QM_TRY_INSPECT(const auto& x,
+                   (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}), QM_VOID,
+                   ([&tryInspectCleanupRan, &aRv](auto& result) {
+                     EXPECT_EQ(result, NS_ERROR_FAILURE);
+
+                     aRv = result;
+
+                     tryInspectCleanupRan = true;
+                   }));
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+
+    aRv = NS_OK;
+  }(rv);
+
+  EXPECT_TRUE(tryInspectCleanupRan);
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, ConstDecl)
+{
+  QM_TRY_INSPECT(const int32_t& x, (Result<int32_t, nsresult>{42}), QM_VOID);
+
+  static_assert(std::is_same_v<decltype(x), const int32_t&>);
+
+  EXPECT_EQ(x, 42);
+}
+
+TEST(QuotaCommon_TryInspect, SameScopeDecl)
+{
+  QM_TRY_INSPECT(const int32_t& x, (Result<int32_t, nsresult>{42}), QM_VOID);
+  EXPECT_EQ(x, 42);
+
+  QM_TRY_INSPECT(const int32_t& y, (Result<int32_t, nsresult>{42}), QM_VOID);
+  EXPECT_EQ(y, 42);
+}
+
+TEST(QuotaCommon_TryInspect, SameLine)
+{
+  // clang-format off
+  QM_TRY_INSPECT(const auto &x, (Result<int32_t, nsresult>{42}), QM_VOID); QM_TRY_INSPECT(const auto &y, (Result<int32_t, nsresult>{42}), QM_VOID);
+  // clang-format on
+
+  EXPECT_EQ(x, 42);
+  EXPECT_EQ(y, 42);
+}
+
+TEST(QuotaCommon_TryInspect, NestingMadness_Success)
+{
+  bool nestedTryInspectDidNotReturn = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&nestedTryInspectDidNotReturn,
+                 &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& x,
+        ([&nestedTryInspectDidNotReturn]() -> Result<int32_t, nsresult> {
+          QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}));
+
+          nestedTryInspectDidNotReturn = true;
+
+          return x;
+        }()));
+    EXPECT_EQ(x, 42);
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTryInspectDidNotReturn);
+  EXPECT_TRUE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_TryInspect, NestingMadness_Failure)
+{
+  bool nestedTryInspectDidNotReturn = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&nestedTryInspectDidNotReturn,
+                 &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& x,
+        ([&nestedTryInspectDidNotReturn]() -> Result<int32_t, nsresult> {
+          QM_TRY_INSPECT(const auto& x,
+                         (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+
+          nestedTryInspectDidNotReturn = true;
+
+          return x;
+        }()));
+    Unused << x;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(nestedTryInspectDidNotReturn);
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, NestingMadness_Multiple_Success)
+{
+  bool nestedTryInspect1DidNotReturn = false;
+  bool nestedTryInspect2DidNotReturn = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&nestedTryInspect1DidNotReturn, &nestedTryInspect2DidNotReturn,
+                 &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& z,
+        ([&nestedTryInspect1DidNotReturn,
+          &nestedTryInspect2DidNotReturn]() -> Result<int32_t, nsresult> {
+          QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}));
+
+          nestedTryInspect1DidNotReturn = true;
+
+          QM_TRY_INSPECT(const auto& y, (Result<int32_t, nsresult>{42}));
+
+          nestedTryInspect2DidNotReturn = true;
+
+          return x + y;
+        }()));
+    EXPECT_EQ(z, 84);
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTryInspect1DidNotReturn);
+  EXPECT_TRUE(nestedTryInspect2DidNotReturn);
+  EXPECT_TRUE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_OK);
+}
+
+TEST(QuotaCommon_TryInspect, NestingMadness_Multiple_Failure1)
+{
+  bool nestedTryInspect1DidNotReturn = false;
+  bool nestedTryInspect2DidNotReturn = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&nestedTryInspect1DidNotReturn, &nestedTryInspect2DidNotReturn,
+                 &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& z,
+        ([&nestedTryInspect1DidNotReturn,
+          &nestedTryInspect2DidNotReturn]() -> Result<int32_t, nsresult> {
+          QM_TRY_INSPECT(const auto& x,
+                         (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+
+          nestedTryInspect1DidNotReturn = true;
+
+          QM_TRY_INSPECT(const auto& y, (Result<int32_t, nsresult>{42}));
+
+          nestedTryInspect2DidNotReturn = true;
+
+          return x + y;
+        }()));
+    Unused << z;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(nestedTryInspect1DidNotReturn);
+  EXPECT_FALSE(nestedTryInspect2DidNotReturn);
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryInspect, NestingMadness_Multiple_Failure2)
+{
+  bool nestedTryInspect1DidNotReturn = false;
+  bool nestedTryInspect2DidNotReturn = false;
+  bool tryInspectDidNotReturn = false;
+
+  nsresult rv = [&nestedTryInspect1DidNotReturn, &nestedTryInspect2DidNotReturn,
+                 &tryInspectDidNotReturn]() -> nsresult {
+    QM_TRY_INSPECT(
+        const auto& z,
+        ([&nestedTryInspect1DidNotReturn,
+          &nestedTryInspect2DidNotReturn]() -> Result<int32_t, nsresult> {
+          QM_TRY_INSPECT(const auto& x, (Result<int32_t, nsresult>{42}));
+
+          nestedTryInspect1DidNotReturn = true;
+
+          QM_TRY_INSPECT(const auto& y,
+                         (Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+
+          nestedTryInspect2DidNotReturn = true;
+
+          return x + y;
+        }()));
+    Unused << z;
+
+    tryInspectDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(nestedTryInspect1DidNotReturn);
+  EXPECT_FALSE(nestedTryInspect2DidNotReturn);
+  EXPECT_FALSE(tryInspectDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+// We are not repeating all QM_TRY_INSPECT test cases for QM_TRY_UNWRAP, since
+// they are largely based on the same implementation. We just add some where
+// inspecting and unwrapping differ.
+
+TEST(QuotaCommon_TryUnwrap, NonConstDecl)
+{
+  QM_TRY_UNWRAP(int32_t x, (Result<int32_t, nsresult>{42}), QM_VOID);
+
+  static_assert(std::is_same_v<decltype(x), int32_t>);
+
+  EXPECT_EQ(x, 42);
+}
+
+TEST(QuotaCommon_TryUnwrap, RvalueDecl)
+{
+  QM_TRY_UNWRAP(int32_t && x, (Result<int32_t, nsresult>{42}), QM_VOID);
+
+  static_assert(std::is_same_v<decltype(x), int32_t&&>);
+
+  EXPECT_EQ(x, 42);
+}
+
+TEST(QuotaCommon_TryUnwrap, ParenDecl)
+{
+  QM_TRY_UNWRAP(
+      (auto&& [x, y]),
+      (Result<std::pair<int32_t, bool>, nsresult>{std::pair{42, true}}),
+      QM_VOID);
+
+  static_assert(std::is_same_v<decltype(x), int32_t>);
+  static_assert(std::is_same_v<decltype(y), bool>);
+
+  EXPECT_EQ(x, 42);
+  EXPECT_EQ(y, true);
+}
+
+TEST(QuotaCommon_TryReturn, Success)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn] {
+    QM_TRY_RETURN((Result<int32_t, nsresult>{42}));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_TryReturn, Success_nsresult)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn] {
+    QM_TRY_RETURN(MOZ_TO_RESULT(NS_OK));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isOk());
+}
+
+#ifdef DEBUG
+TEST(QuotaCommon_TryReturn, Success_CustomErr_AssertUnreachable)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn]() -> Result<int32_t, nsresult> {
+    QM_TRY_RETURN((Result<int32_t, nsresult>{42}), QM_ASSERT_UNREACHABLE);
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+#endif
+
+TEST(QuotaCommon_TryReturn, Success_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                                \
+  {                                                                 \
+    bool tryReturnDidNotReturn = false;                             \
+                                                                    \
+    auto res = [&tryReturnDidNotReturn]() -> Result<Ok, nsresult> { \
+      QM_TRY_RETURN(MOZ_TO_RESULT(NS_OK),                           \
+                    [](__VA_ARGS__) { return Err(aRv); });          \
+                                                                    \
+      tryReturnDidNotReturn = true;                                 \
+    }();                                                            \
+                                                                    \
+    EXPECT_FALSE(tryReturnDidNotReturn);                            \
+    EXPECT_TRUE(res.isOk());                                        \
+  }
+
+  SUBTEST(const char*, nsresult aRv);
+  SUBTEST(nsresult aRv);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_TryReturn, Success_WithCleanup)
+{
+  bool tryReturnCleanupRan = false;
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnCleanupRan,
+              &tryReturnDidNotReturn]() -> Result<int32_t, nsresult> {
+    QM_TRY_RETURN(
+        (Result<int32_t, nsresult>{42}), QM_PROPAGATE,
+        [&tryReturnCleanupRan](const auto&) { tryReturnCleanupRan = true; });
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnCleanupRan);
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_TryReturn, Failure_PropagateErr)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn] {
+    QM_TRY_RETURN((Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryReturn, Failure_PropagateErr_nsresult)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn] {
+    QM_TRY_RETURN(MOZ_TO_RESULT(NS_ERROR_FAILURE));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryReturn, Failure_CustomErr)
+{
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnDidNotReturn]() -> Result<int32_t, nsresult> {
+    QM_TRY_RETURN((Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}),
+                  Err(NS_ERROR_UNEXPECTED));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_TryReturn, Failure_CustomErr_CustomLambda)
+{
+#define SUBTEST(...)                                                       \
+  {                                                                        \
+    bool tryReturnDidNotReturn = false;                                    \
+                                                                           \
+    auto res = [&tryReturnDidNotReturn]() -> Result<int32_t, nsresult> {   \
+      QM_TRY_RETURN((Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}),    \
+                    [](__VA_ARGS__) { return Err(NS_ERROR_UNEXPECTED); }); \
+                                                                           \
+      tryReturnDidNotReturn = true;                                        \
+    }();                                                                   \
+                                                                           \
+    EXPECT_FALSE(tryReturnDidNotReturn);                                   \
+    EXPECT_TRUE(res.isErr());                                              \
+    EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);                       \
+  }
+
+  SUBTEST(const char*, nsresult);
+  SUBTEST(nsresult);
+
+#undef SUBTEST
+}
+
+TEST(QuotaCommon_TryReturn, Failure_WithCleanup)
+{
+  bool tryReturnCleanupRan = false;
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&tryReturnCleanupRan,
+              &tryReturnDidNotReturn]() -> Result<int32_t, nsresult> {
+    QM_TRY_RETURN((Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}),
+                  QM_PROPAGATE, [&tryReturnCleanupRan](const auto& result) {
+                    EXPECT_EQ(result, NS_ERROR_FAILURE);
+
+                    tryReturnCleanupRan = true;
+                  });
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_TRUE(tryReturnCleanupRan);
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_TryReturn, SameLine)
+{
+  // clang-format off
+  auto res1 = [] { QM_TRY_RETURN((Result<int32_t, nsresult>{42})); }(); auto res2 = []() -> Result<int32_t, nsresult> { QM_TRY_RETURN((Result<int32_t, nsresult>{42})); }();
+  // clang-format on
+
+  EXPECT_TRUE(res1.isOk());
+  EXPECT_EQ(res1.unwrap(), 42);
+  EXPECT_TRUE(res2.isOk());
+  EXPECT_EQ(res2.unwrap(), 42);
+}
+
+TEST(QuotaCommon_TryReturn, NestingMadness_Success)
+{
+  bool nestedTryReturnDidNotReturn = false;
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&nestedTryReturnDidNotReturn, &tryReturnDidNotReturn] {
+    QM_TRY_RETURN(([&nestedTryReturnDidNotReturn] {
+      QM_TRY_RETURN((Result<int32_t, nsresult>{42}));
+
+      nestedTryReturnDidNotReturn = true;
+    }()));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(nestedTryReturnDidNotReturn);
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_TryReturn, NestingMadness_Failure)
+{
+  bool nestedTryReturnDidNotReturn = false;
+  bool tryReturnDidNotReturn = false;
+
+  auto res = [&nestedTryReturnDidNotReturn, &tryReturnDidNotReturn] {
+    QM_TRY_RETURN(([&nestedTryReturnDidNotReturn] {
+      QM_TRY_RETURN((Result<int32_t, nsresult>{Err(NS_ERROR_FAILURE)}));
+
+      nestedTryReturnDidNotReturn = true;
+    }()));
+
+    tryReturnDidNotReturn = true;
+  }();
+
+  EXPECT_FALSE(nestedTryReturnDidNotReturn);
+  EXPECT_FALSE(tryReturnDidNotReturn);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Fail, ReturnValue)
+{
+  bool failDidNotReturn = false;
+
+  nsresult rv = [&failDidNotReturn]() -> nsresult {
+    QM_FAIL(NS_ERROR_FAILURE);
+
+    failDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_FALSE(failDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_Fail, ReturnValue_WithCleanup)
+{
+  bool failCleanupRan = false;
+  bool failDidNotReturn = false;
+
+  nsresult rv = [&failCleanupRan, &failDidNotReturn]() -> nsresult {
+    QM_FAIL(NS_ERROR_FAILURE, [&failCleanupRan]() { failCleanupRan = true; });
+
+    failDidNotReturn = true;
+
+    return NS_OK;
+  }();
+
+  EXPECT_TRUE(failCleanupRan);
+  EXPECT_FALSE(failDidNotReturn);
+  EXPECT_EQ(rv, NS_ERROR_FAILURE);
+}
+
+TEST(QuotaCommon_WarnOnlyTry, Success)
+{
+  bool warnOnlyTryDidNotReturn = false;
+
+  const auto res =
+      [&warnOnlyTryDidNotReturn]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY(OkIf(true));
+
+    warnOnlyTryDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTry, Success_WithCleanup)
+{
+  bool warnOnlyTryCleanupRan = false;
+  bool warnOnlyTryDidNotReturn = false;
+
+  const auto res =
+      [&warnOnlyTryCleanupRan,
+       &warnOnlyTryDidNotReturn]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY(OkIf(true), [&warnOnlyTryCleanupRan](const auto&) {
+      warnOnlyTryCleanupRan = true;
+    });
+
+    warnOnlyTryDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_FALSE(warnOnlyTryCleanupRan);
+  EXPECT_TRUE(warnOnlyTryDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTry, Failure)
+{
+  bool warnOnlyTryDidNotReturn = false;
+
+  const auto res =
+      [&warnOnlyTryDidNotReturn]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY(OkIf(false));
+
+    warnOnlyTryDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTry, Failure_WithCleanup)
+{
+  bool warnOnlyTryCleanupRan = false;
+  bool warnOnlyTryDidNotReturn = false;
+
+  const auto res =
+      [&warnOnlyTryCleanupRan,
+       &warnOnlyTryDidNotReturn]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY(OkIf(false), ([&warnOnlyTryCleanupRan](const auto&) {
+                      warnOnlyTryCleanupRan = true;
+                    }));
+
+    warnOnlyTryDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryCleanupRan);
+  EXPECT_TRUE(warnOnlyTryDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTryUnwrap, Success)
+{
+  bool warnOnlyTryUnwrapDidNotReturn = false;
+
+  const auto res = [&warnOnlyTryUnwrapDidNotReturn]()
+      -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY_UNWRAP(const auto x, (Result<int32_t, NotOk>{42}));
+    EXPECT_TRUE(x);
+    EXPECT_EQ(*x, 42);
+
+    warnOnlyTryUnwrapDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryUnwrapDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTryUnwrap, Success_WithCleanup)
+{
+  bool warnOnlyTryUnwrapCleanupRan = false;
+  bool warnOnlyTryUnwrapDidNotReturn = false;
+
+  const auto res = [&warnOnlyTryUnwrapCleanupRan,
+                    &warnOnlyTryUnwrapDidNotReturn]()
+      -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY_UNWRAP(const auto x, (Result<int32_t, NotOk>{42}),
+                           [&warnOnlyTryUnwrapCleanupRan](const auto&) {
+                             warnOnlyTryUnwrapCleanupRan = true;
+                           });
+    EXPECT_TRUE(x);
+    EXPECT_EQ(*x, 42);
+
+    warnOnlyTryUnwrapDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_FALSE(warnOnlyTryUnwrapCleanupRan);
+  EXPECT_TRUE(warnOnlyTryUnwrapDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTryUnwrap, Failure)
+{
+  bool warnOnlyTryUnwrapDidNotReturn = false;
+
+  const auto res = [&warnOnlyTryUnwrapDidNotReturn]()
+      -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY_UNWRAP(const auto x,
+                           (Result<int32_t, NotOk>{Err(NotOk{})}));
+    EXPECT_FALSE(x);
+
+    warnOnlyTryUnwrapDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryUnwrapDidNotReturn);
+}
+
+TEST(QuotaCommon_WarnOnlyTryUnwrap, Failure_WithCleanup)
+{
+  bool warnOnlyTryUnwrapCleanupRan = false;
+  bool warnOnlyTryUnwrapDidNotReturn = false;
+
+  const auto res = [&warnOnlyTryUnwrapCleanupRan,
+                    &warnOnlyTryUnwrapDidNotReturn]()
+      -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_WARNONLY_TRY_UNWRAP(const auto x, (Result<int32_t, NotOk>{Err(NotOk{})}),
+                           [&warnOnlyTryUnwrapCleanupRan](const auto&) {
+                             warnOnlyTryUnwrapCleanupRan = true;
+                           });
+    EXPECT_FALSE(x);
+
+    warnOnlyTryUnwrapDidNotReturn = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(warnOnlyTryUnwrapCleanupRan);
+  EXPECT_TRUE(warnOnlyTryUnwrapDidNotReturn);
+}
+
+TEST(QuotaCommon_OrElseWarn, Success)
+{
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN(OkIf(true), ([&fallbackRun](const NotOk) {
+                             fallbackRun = true;
+                             return mozilla::Result<mozilla::Ok, NotOk>{
+                                 mozilla::Ok{}};
+                           })));
+
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_FALSE(fallbackRun);
+  EXPECT_TRUE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarn, Failure_MappedToSuccess)
+{
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  // XXX Consider allowing to set a custom error handler, so that we can
+  // actually assert that a warning was emitted.
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN(OkIf(false), ([&fallbackRun](const NotOk) {
+                             fallbackRun = true;
+                             return mozilla::Result<mozilla::Ok, NotOk>{
+                                 mozilla::Ok{}};
+                           })));
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(fallbackRun);
+  EXPECT_TRUE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarn, Failure_MappedToError)
+{
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  // XXX Consider allowing to set a custom error handler, so that we can
+  // actually assert that a warning was emitted.
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN(OkIf(false), ([&fallbackRun](const NotOk) {
+                             fallbackRun = true;
+                             return mozilla::Result<mozilla::Ok, NotOk>{
+                                 NotOk{}};
+                           })));
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_TRUE(fallbackRun);
+  EXPECT_FALSE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarnIf, Success)
+{
+  bool predicateRun = false;
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN_IF(
+        OkIf(true),
+        [&predicateRun](const NotOk) {
+          predicateRun = true;
+          return false;
+        },
+        ([&fallbackRun](const NotOk) {
+          fallbackRun = true;
+          return mozilla::Result<mozilla::Ok, NotOk>{mozilla::Ok{}};
+        })));
+
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_FALSE(predicateRun);
+  EXPECT_FALSE(fallbackRun);
+  EXPECT_TRUE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarnIf, Failure_PredicateReturnsFalse)
+{
+  bool predicateRun = false;
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN_IF(
+        OkIf(false),
+        [&predicateRun](const NotOk) {
+          predicateRun = true;
+          return false;
+        },
+        ([&fallbackRun](const NotOk) {
+          fallbackRun = true;
+          return mozilla::Result<mozilla::Ok, NotOk>{mozilla::Ok{}};
+        })));
+
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_TRUE(predicateRun);
+  EXPECT_FALSE(fallbackRun);
+  EXPECT_FALSE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarnIf, Failure_PredicateReturnsTrue_MappedToSuccess)
+{
+  bool predicateRun = false;
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN_IF(
+        OkIf(false),
+        [&predicateRun](const NotOk) {
+          predicateRun = true;
+          return true;
+        },
+        ([&fallbackRun](const NotOk) {
+          fallbackRun = true;
+          return mozilla::Result<mozilla::Ok, NotOk>{mozilla::Ok{}};
+        })));
+
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_TRUE(predicateRun);
+  EXPECT_TRUE(fallbackRun);
+  EXPECT_TRUE(tryContinued);
+}
+
+TEST(QuotaCommon_OrElseWarnIf, Failure_PredicateReturnsTrue_MappedToError)
+{
+  bool predicateRun = false;
+  bool fallbackRun = false;
+  bool tryContinued = false;
+
+  const auto res = [&]() -> mozilla::Result<mozilla::Ok, NotOk> {
+    QM_TRY(QM_OR_ELSE_WARN_IF(
+        OkIf(false),
+        [&predicateRun](const NotOk) {
+          predicateRun = true;
+          return true;
+        },
+        ([&fallbackRun](const NotOk) {
+          fallbackRun = true;
+          return mozilla::Result<mozilla::Ok, NotOk>{mozilla::NotOk{}};
+        })));
+
+    tryContinued = true;
+    return mozilla::Ok{};
+  }();
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_TRUE(predicateRun);
+  EXPECT_TRUE(fallbackRun);
+  EXPECT_FALSE(tryContinued);
+}
+
+TEST(QuotaCommon_OkIf, True)
+{
+  auto res = OkIf(true);
+
+  EXPECT_TRUE(res.isOk());
+}
+
+TEST(QuotaCommon_OkIf, False)
+{
+  auto res = OkIf(false);
+
+  EXPECT_TRUE(res.isErr());
+}
+
+TEST(QuotaCommon_OkToOk, Bool_True)
+{
+  auto res = OkToOk<true>(Ok());
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), true);
+}
+
+TEST(QuotaCommon_OkToOk, Bool_False)
+{
+  auto res = OkToOk<false>(Ok());
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), false);
+}
+
+TEST(QuotaCommon_OkToOk, Int_42)
+{
+  auto res = OkToOk<42>(Ok());
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Bool_True)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, true>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), true);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Bool_True_Err)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, true>(NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Bool_False)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, false>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), false);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Bool_False_Err)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, false>(NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Int_42)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, 42>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, Int_42_Err)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, 42>(NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, NsCOMPtr_nullptr)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, nullptr, nsCOMPtr<nsISupports>>(
+      NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), nullptr);
+}
+
+TEST(QuotaCommon_ErrToOkOrErr, NsCOMPtr_nullptr_Err)
+{
+  auto res = ErrToOkOrErr<NS_ERROR_FAILURE, nullptr, nsCOMPtr<nsISupports>>(
+      NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_ErrToDefaultOkOrErr, Ok)
+{
+  auto res = ErrToDefaultOkOrErr<NS_ERROR_FAILURE, Ok>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+}
+
+TEST(QuotaCommon_ErrToDefaultOkOrErr, Ok_Err)
+{
+  auto res = ErrToDefaultOkOrErr<NS_ERROR_FAILURE, Ok>(NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_ErrToDefaultOkOrErr, NsCOMPtr)
+{
+  auto res = ErrToDefaultOkOrErr<NS_ERROR_FAILURE, nsCOMPtr<nsISupports>>(
+      NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), nullptr);
+}
+
+TEST(QuotaCommon_ErrToDefaultOkOrErr, NsCOMPtr_Err)
+{
+  auto res = ErrToDefaultOkOrErr<NS_ERROR_FAILURE, nsCOMPtr<nsISupports>>(
+      NS_ERROR_UNEXPECTED);
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_UNEXPECTED);
+}
+
+TEST(QuotaCommon_IsSpecificError, Match)
+{ EXPECT_TRUE(IsSpecificError<NS_ERROR_FAILURE>(NS_ERROR_FAILURE)); }
+
+TEST(QuotaCommon_IsSpecificError, Mismatch)
+{ EXPECT_FALSE(IsSpecificError<NS_ERROR_FAILURE>(NS_ERROR_UNEXPECTED)); }
+
+TEST(QuotaCommon_ErrToOk, Bool_True)
+{
+  auto res = ErrToOk<true>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), true);
+}
+
+TEST(QuotaCommon_ErrToOk, Bool_False)
+{
+  auto res = ErrToOk<false>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), false);
+}
+
+TEST(QuotaCommon_ErrToOk, Int_42)
+{
+  auto res = ErrToOk<42>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(QuotaCommon_ErrToOk, NsCOMPtr_nullptr)
+{
+  auto res = ErrToOk<nullptr, nsCOMPtr<nsISupports>>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), nullptr);
+}
+
+TEST(QuotaCommon_ErrToDefaultOk, Ok)
+{
+  auto res = ErrToDefaultOk<Ok>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+}
+
+TEST(QuotaCommon_ErrToDefaultOk, NsCOMPtr)
+{
+  auto res = ErrToDefaultOk<nsCOMPtr<nsISupports>>(NS_ERROR_FAILURE);
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), nullptr);
+}
+
+class StringPairParameterized
+    : public ::testing::TestWithParam<std::pair<const char*, const char*>> {};
+
+TEST_P(StringPairParameterized, AnonymizedOriginString) {
+  const auto [in, expectedAnonymized] = GetParam();
+  const auto anonymized = AnonymizedOriginString(nsDependentCString(in));
+  EXPECT_STREQ(anonymized.get(), expectedAnonymized);
+}
+
+INSTANTIATE_TEST_SUITE_P(
+    QuotaCommon, StringPairParameterized,
+    ::testing::Values(
+        // XXX Do we really want to anonymize about: origins?
+        std::pair("about:home", "about:aaaa"),
+        std::pair("https://foo.bar.com", "https://aaa.aaa.aaa"),
+        std::pair("https://foo.bar.com:8000", "https://aaa.aaa.aaa:DDDD"),
+        std::pair("file://UNIVERSAL_FILE_ORIGIN",
+                  "file://aaaaaaaaa_aaaa_aaaaaa")));
+
+// BEGIN COPY FROM mfbt/tests/TestResult.cpp
+struct Failed {};
+
+static GenericErrorResult<Failed> Fail() { return Err(Failed()); }
+
+static Result<Ok, Failed> Task1(bool pass) {
+  if (!pass) {
+    return Fail();  // implicit conversion from GenericErrorResult to Result
+  }
+  return Ok();
+}
+// END COPY FROM mfbt/tests/TestResult.cpp
+
+static Result<bool, Failed> Condition(bool aNoError, bool aResult) {
+  return Task1(aNoError).map([aResult](auto) { return aResult; });
+}
+
+TEST(QuotaCommon_CollectWhileTest, NoFailures)
+{
+  const size_t loopCount = 5;
+  size_t conditionExecutions = 0;
+  size_t bodyExecutions = 0;
+  auto result = CollectWhile(
+      [&conditionExecutions] {
+        ++conditionExecutions;
+        return Condition(true, conditionExecutions <= loopCount);
+      },
+      [&bodyExecutions] {
+        ++bodyExecutions;
+        return Task1(true);
+      });
+  static_assert(std::is_same_v<decltype(result), Result<Ok, Failed>>);
+  MOZ_RELEASE_ASSERT(result.isOk());
+  MOZ_RELEASE_ASSERT(loopCount == bodyExecutions);
+  MOZ_RELEASE_ASSERT(1 + loopCount == conditionExecutions);
+}
+
+TEST(QuotaCommon_CollectWhileTest, BodyFailsImmediately)
+{
+  size_t conditionExecutions = 0;
+  size_t bodyExecutions = 0;
+  auto result = CollectWhile(
+      [&conditionExecutions] {
+        ++conditionExecutions;
+        return Condition(true, true);
+      },
+      [&bodyExecutions] {
+        ++bodyExecutions;
+        return Task1(false);
+      });
+  static_assert(std::is_same_v<decltype(result), Result<Ok, Failed>>);
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(1 == bodyExecutions);
+  MOZ_RELEASE_ASSERT(1 == conditionExecutions);
+}
+
+TEST(QuotaCommon_CollectWhileTest, BodyFailsOnSecondExecution)
+{
+  size_t conditionExecutions = 0;
+  size_t bodyExecutions = 0;
+  auto result = CollectWhile(
+      [&conditionExecutions] {
+        ++conditionExecutions;
+        return Condition(true, true);
+      },
+      [&bodyExecutions] {
+        ++bodyExecutions;
+        return Task1(bodyExecutions < 2);
+      });
+  static_assert(std::is_same_v<decltype(result), Result<Ok, Failed>>);
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(2 == bodyExecutions);
+  MOZ_RELEASE_ASSERT(2 == conditionExecutions);
+}
+
+TEST(QuotaCommon_CollectWhileTest, ConditionFailsImmediately)
+{
+  size_t conditionExecutions = 0;
+  size_t bodyExecutions = 0;
+  auto result = CollectWhile(
+      [&conditionExecutions] {
+        ++conditionExecutions;
+        return Condition(false, true);
+      },
+      [&bodyExecutions] {
+        ++bodyExecutions;
+        return Task1(true);
+      });
+  static_assert(std::is_same_v<decltype(result), Result<Ok, Failed>>);
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(0 == bodyExecutions);
+  MOZ_RELEASE_ASSERT(1 == conditionExecutions);
+}
+
+TEST(QuotaCommon_CollectWhileTest, ConditionFailsOnSecondExecution)
+{
+  size_t conditionExecutions = 0;
+  size_t bodyExecutions = 0;
+  auto result = CollectWhile(
+      [&conditionExecutions] {
+        ++conditionExecutions;
+        return Condition(conditionExecutions < 2, true);
+      },
+      [&bodyExecutions] {
+        ++bodyExecutions;
+        return Task1(true);
+      });
+  static_assert(std::is_same_v<decltype(result), Result<Ok, Failed>>);
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(1 == bodyExecutions);
+  MOZ_RELEASE_ASSERT(2 == conditionExecutions);
+}
+
+TEST(QuotaCommon_CollectEachInRange, Success)
+{
+  size_t bodyExecutions = 0;
+  const auto result = CollectEachInRange(
+      std::array<int, 5>{{1, 2, 3, 4, 5}},
+      [&bodyExecutions](const int val) -> Result<Ok, nsresult> {
+        ++bodyExecutions;
+        return Ok{};
+      });
+
+  MOZ_RELEASE_ASSERT(result.isOk());
+  MOZ_RELEASE_ASSERT(5 == bodyExecutions);
+}
+
+TEST(QuotaCommon_CollectEachInRange, FailureShortCircuit)
+{
+  size_t bodyExecutions = 0;
+  const auto result = CollectEachInRange(
+      std::array<int, 5>{{1, 2, 3, 4, 5}},
+      [&bodyExecutions](const int val) -> Result<Ok, nsresult> {
+        ++bodyExecutions;
+        return val == 3 ? Err(NS_ERROR_FAILURE) : Result<Ok, nsresult>{Ok{}};
+      });
+
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(NS_ERROR_FAILURE == result.inspectErr());
+  MOZ_RELEASE_ASSERT(3 == bodyExecutions);
+}
+
+TEST(QuotaCommon_ReduceEach, Success)
+{
+  const auto result = ReduceEach(
+      [i = int{0}]() mutable -> Result<int, Failed> {
+        if (i < 5) {
+          return ++i;
+        }
+        return 0;
+      },
+      0, [](int val, int add) -> Result<int, Failed> { return val + add; });
+  static_assert(std::is_same_v<decltype(result), const Result<int, Failed>>);
+
+  MOZ_RELEASE_ASSERT(result.isOk());
+  MOZ_RELEASE_ASSERT(15 == result.inspect());
+}
+
+TEST(QuotaCommon_ReduceEach, StepError)
+{
+  const auto result = ReduceEach(
+      [i = int{0}]() mutable -> Result<int, Failed> {
+        if (i < 5) {
+          return ++i;
+        }
+        return 0;
+      },
+      0,
+      [](int val, int add) -> Result<int, Failed> {
+        if (val > 2) {
+          return Err(Failed{});
+        }
+        return val + add;
+      });
+  static_assert(std::is_same_v<decltype(result), const Result<int, Failed>>);
+
+  MOZ_RELEASE_ASSERT(result.isErr());
+}
+
+TEST(QuotaCommon_ReduceEach, GeneratorError)
+{
+  size_t generatorExecutions = 0;
+  const auto result = ReduceEach(
+      [i = int{0}, &generatorExecutions]() mutable -> Result<int, Failed> {
+        ++generatorExecutions;
+        if (i < 1) {
+          return ++i;
+        }
+        return Err(Failed{});
+      },
+      0,
+      [](int val, int add) -> Result<int, Failed> {
+        if (val > 2) {
+          return Err(Failed{});
+        }
+        return val + add;
+      });
+  static_assert(std::is_same_v<decltype(result), const Result<int, Failed>>);
+
+  MOZ_RELEASE_ASSERT(result.isErr());
+  MOZ_RELEASE_ASSERT(2 == generatorExecutions);
+}
+
+TEST(QuotaCommon_Reduce, Success)
+{
+  const auto range = std::vector{0, 1, 2, 3, 4, 5};
+  const auto result = Reduce(
+      range, 0, [](int val, Maybe<const int&> add) -> Result<int, Failed> {
+        return val + add.ref();
+      });
+  static_assert(std::is_same_v<decltype(result), const Result<int, Failed>>);
+
+  MOZ_RELEASE_ASSERT(result.isOk());
+  MOZ_RELEASE_ASSERT(15 == result.inspect());
+}
+
+TEST(QuotaCommon_CallWithDelayedRetriesIfAccessDenied, NoFailures)
+{
+  uint32_t tries = 0;
+
+  auto res = CallWithDelayedRetriesIfAccessDenied(
+      [&tries]() -> Result<Ok, nsresult> {
+        ++tries;
+        return Ok{};
+      },
+      10, 2);
+
+  EXPECT_EQ(tries, 1u);
+  EXPECT_TRUE(res.isOk());
+}
+
+TEST(QuotaCommon_CallWithDelayedRetriesIfAccessDenied, PermanentFailures)
+{
+  uint32_t tries = 0;
+
+  auto res = CallWithDelayedRetriesIfAccessDenied(
+      [&tries]() -> Result<Ok, nsresult> {
+        ++tries;
+        return Err(NS_ERROR_FILE_IS_LOCKED);
+      },
+      10, 2);
+
+  EXPECT_EQ(tries, 11u);
+  EXPECT_TRUE(res.isErr());
+}
+
+TEST(QuotaCommon_CallWithDelayedRetriesIfAccessDenied, FailuresAndSuccess)
+{
+  uint32_t tries = 0;
+
+  auto res = CallWithDelayedRetriesIfAccessDenied(
+      [&tries]() -> Result<Ok, nsresult> {
+        if (++tries == 5) {
+          return Ok{};
+        }
+        return Err(NS_ERROR_FILE_ACCESS_DENIED);
+      },
+      10, 2);
+
+  EXPECT_EQ(tries, 5u);
+  EXPECT_TRUE(res.isOk());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, ThisSourceFile)
+{
+  static constexpr auto thisSourceFileRelativePath =
+      "dom/quota/test/gtest/TestQuotaCommon.cpp"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          nsLiteralCString(__FILE__))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(), thisSourceFileRelativePath.get());
+}
+
+static nsCString MakeTreePath(const nsACString& aBasePath,
+                              const nsACString& aRelativePath) {
+  nsCString path{aBasePath};
+
+  path.Append("/");
+  path.Append(aRelativePath);
+
+  return path;
+}
+
+static nsCString MakeSourceTreePath(const nsACString& aRelativePath) {
+  return MakeTreePath(mozilla::dom::quota::detail::GetSourceTreeBase(),
+                      aRelativePath);
+}
+
+static nsCString MakeObjdirDistIncludeTreePath(
+    const nsACString& aRelativePath) {
+  return MakeTreePath(
+      mozilla::dom::quota::detail::GetObjdirDistIncludeTreeBase(),
+      aRelativePath);
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, DomQuotaSourceFile)
+{
+  static constexpr auto domQuotaSourceFileRelativePath =
+      "dom/quota/ActorsParent.cpp"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          MakeSourceTreePath(domQuotaSourceFileRelativePath))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(),
+               domQuotaSourceFileRelativePath.get());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, DomQuotaSourceFile_Exported)
+{
+  static constexpr auto mozillaDomQuotaSourceFileRelativePath =
+      "mozilla/dom/quota/QuotaCommon.h"_ns;
+
+  static constexpr auto domQuotaSourceFileRelativePath =
+      "dom/quota/QuotaCommon.h"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          MakeObjdirDistIncludeTreePath(
+              mozillaDomQuotaSourceFileRelativePath))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(),
+               domQuotaSourceFileRelativePath.get());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, DomIndexedDBSourceFile)
+{
+  static constexpr auto domIndexedDBSourceFileRelativePath =
+      "dom/indexedDB/ActorsParent.cpp"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          MakeSourceTreePath(domIndexedDBSourceFileRelativePath))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(),
+               domIndexedDBSourceFileRelativePath.get());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath,
+     DomLocalstorageSourceFile_Exported_Mapped)
+{
+  static constexpr auto mozillaDomSourceFileRelativePath =
+      "mozilla/dom/LocalStorageCommon.h"_ns;
+
+  static constexpr auto domLocalstorageSourceFileRelativePath =
+      "dom/localstorage/LocalStorageCommon.h"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          MakeObjdirDistIncludeTreePath(mozillaDomSourceFileRelativePath))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(),
+               domLocalstorageSourceFileRelativePath.get());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, NonDomSourceFile)
+{
+  static constexpr auto nonDomSourceFileRelativePath =
+      "storage/mozStorageService.cpp"_ns;
+
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          MakeSourceTreePath(nonDomSourceFileRelativePath))};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(),
+               nonDomSourceFileRelativePath.get());
+}
+
+TEST(QuotaCommon_MakeSourceFileRelativePath, OtherSourceFile)
+{
+  constexpr auto otherSourceFilePath = "/foo/bar/Test.cpp"_ns;
+  const nsCString sourceFileRelativePath{
+      mozilla::dom::quota::detail::MakeSourceFileRelativePath(
+          otherSourceFilePath)};
+
+  EXPECT_STREQ(sourceFileRelativePath.get(), "Test.cpp");
+}
+
+#ifdef __clang__
+#  pragma clang diagnostic pop
+#endif
diff --git a/dom/quota/test/gtest/TestQuotaManager.cpp b/dom/quota/test/gtest/TestQuotaManager.cpp
new file mode 100644
index 0000000000..7d185df481
--- /dev/null
+++ b/dom/quota/test/gtest/TestQuotaManager.cpp
@@ -0,0 +1,181 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/OriginScope.h"
+
+#include "gtest/gtest.h"
+
+#include <cstdint>
+#include <memory>
+#include "ErrorList.h"
+#include "mozilla/Result.h"
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "mozilla/fallible.h"
+#include "nsCOMPtr.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
+#include "nsIFile.h"
+#include "nsLiteralString.h"
+#include "nsString.h"
+#include "nsStringFwd.h"
+#include "nsTLiteralString.h"
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+namespace {
+
+struct OriginTest {
+  const char* mOrigin;
+  bool mMatch;
+};
+
+void CheckOriginScopeMatchesOrigin(const OriginScope& aOriginScope,
+                                   const char* aOrigin, bool aMatch) {
+  bool result = aOriginScope.Matches(
+      OriginScope::FromOrigin(nsDependentCString(aOrigin)));
+
+  EXPECT_TRUE(result == aMatch);
+}
+
+void CheckUnknownFileEntry(nsIFile& aBase, const nsAString& aName,
+                           const bool aWarnIfFile, const bool aWarnIfDir) {
+  nsCOMPtr<nsIFile> file;
+  nsresult rv = aBase.Clone(getter_AddRefs(file));
+  ASSERT_EQ(rv, NS_OK);
+
+  rv = file->Append(aName);
+  ASSERT_EQ(rv, NS_OK);
+
+  rv = file->Create(nsIFile::NORMAL_FILE_TYPE, 0600);
+  ASSERT_EQ(rv, NS_OK);
+
+  auto okOrErr = WARN_IF_FILE_IS_UNKNOWN(*file);
+  ASSERT_TRUE(okOrErr.isOk());
+
+#ifdef DEBUG
+  EXPECT_TRUE(okOrErr.inspect() == aWarnIfFile);
+#else
+  EXPECT_TRUE(okOrErr.inspect() == false);
+#endif
+
+  rv = file->Remove(false);
+  ASSERT_EQ(rv, NS_OK);
+
+  rv = file->Create(nsIFile::DIRECTORY_TYPE, 0700);
+  ASSERT_EQ(rv, NS_OK);
+
+  okOrErr = WARN_IF_FILE_IS_UNKNOWN(*file);
+  ASSERT_TRUE(okOrErr.isOk());
+
+#ifdef DEBUG
+  EXPECT_TRUE(okOrErr.inspect() == aWarnIfDir);
+#else
+  EXPECT_TRUE(okOrErr.inspect() == false);
+#endif
+
+  rv = file->Remove(false);
+  ASSERT_EQ(rv, NS_OK);
+}
+
+}  // namespace
+
+TEST(QuotaManager, OriginScope)
+{
+  OriginScope originScope;
+
+  // Sanity checks.
+
+  {
+    constexpr auto origin = "http://www.mozilla.org"_ns;
+    originScope.SetFromOrigin(origin);
+    EXPECT_TRUE(originScope.IsOrigin());
+    EXPECT_TRUE(originScope.GetOrigin().Equals(origin));
+    EXPECT_TRUE(originScope.GetOriginNoSuffix().Equals(origin));
+  }
+
+  {
+    constexpr auto prefix = "http://www.mozilla.org"_ns;
+    originScope.SetFromPrefix(prefix);
+    EXPECT_TRUE(originScope.IsPrefix());
+    EXPECT_TRUE(originScope.GetOriginNoSuffix().Equals(prefix));
+  }
+
+  {
+    originScope.SetFromNull();
+    EXPECT_TRUE(originScope.IsNull());
+  }
+
+  // Test each origin scope type against particular origins.
+
+  {
+    originScope.SetFromOrigin("http://www.mozilla.org"_ns);
+
+    static const OriginTest tests[] = {
+        {"http://www.mozilla.org", true},
+        {"http://www.example.org", false},
+    };
+
+    for (const auto& test : tests) {
+      CheckOriginScopeMatchesOrigin(originScope, test.mOrigin, test.mMatch);
+    }
+  }
+
+  {
+    originScope.SetFromPrefix("http://www.mozilla.org"_ns);
+
+    static const OriginTest tests[] = {
+        {"http://www.mozilla.org", true},
+        {"http://www.mozilla.org^userContextId=1", true},
+        {"http://www.example.org^userContextId=1", false},
+    };
+
+    for (const auto& test : tests) {
+      CheckOriginScopeMatchesOrigin(originScope, test.mOrigin, test.mMatch);
+    }
+  }
+
+  {
+    originScope.SetFromNull();
+
+    static const OriginTest tests[] = {
+        {"http://www.mozilla.org", true},
+        {"http://www.mozilla.org^userContextId=1", true},
+        {"http://www.example.org^userContextId=1", true},
+    };
+
+    for (const auto& test : tests) {
+      CheckOriginScopeMatchesOrigin(originScope, test.mOrigin, test.mMatch);
+    }
+  }
+}
+
+TEST(QuotaManager, WarnIfUnknownFile)
+{
+  nsCOMPtr<nsIFile> base;
+  nsresult rv = NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(base));
+  ASSERT_EQ(rv, NS_OK);
+
+  rv = base->Append(u"mozquotatests"_ns);
+  ASSERT_EQ(rv, NS_OK);
+
+  base->Remove(true);
+
+  rv = base->Create(nsIFile::DIRECTORY_TYPE, 0700);
+  ASSERT_EQ(rv, NS_OK);
+
+  CheckUnknownFileEntry(*base, u"foo.bar"_ns, true, true);
+  CheckUnknownFileEntry(*base, u".DS_Store"_ns, false, true);
+  CheckUnknownFileEntry(*base, u".desktop"_ns, false, true);
+  CheckUnknownFileEntry(*base, u"desktop.ini"_ns, false, true);
+  CheckUnknownFileEntry(*base, u"DESKTOP.INI"_ns, false, true);
+  CheckUnknownFileEntry(*base, u"thumbs.db"_ns, false, true);
+  CheckUnknownFileEntry(*base, u"THUMBS.DB"_ns, false, true);
+  CheckUnknownFileEntry(*base, u".xyz"_ns, false, true);
+
+  rv = base->Remove(true);
+  ASSERT_EQ(rv, NS_OK);
+}
diff --git a/dom/quota/test/gtest/TestResultExtensions.cpp b/dom/quota/test/gtest/TestResultExtensions.cpp
new file mode 100644
index 0000000000..137acc1423
--- /dev/null
+++ b/dom/quota/test/gtest/TestResultExtensions.cpp
@@ -0,0 +1,333 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Common.h"
+#include "gtest/gtest.h"
+#include "mozilla/dom/QMResult.h"
+#include "mozilla/dom/quota/ResultExtensions.h"
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+namespace {
+class TestClass {
+ public:
+  static constexpr int kTestValue = 42;
+
+  nsresult NonOverloadedNoInputComplex(std::pair<int, int>* aOut) {
+    *aOut = std::pair{kTestValue, kTestValue};
+    return NS_OK;
+  }
+  nsresult NonOverloadedNoInputFailsComplex(std::pair<int, int>* aOut) {
+    return NS_ERROR_FAILURE;
+  }
+};
+}  // namespace
+
+class DOM_Quota_ResultExtensions_ToResult : public DOM_Quota_Test {};
+class DOM_Quota_ResultExtensions_GenericErrorResult : public DOM_Quota_Test {};
+
+TEST_F(DOM_Quota_ResultExtensions_ToResult, FromBool) {
+  // success
+  {
+    auto res = ToResult(true);
+    static_assert(std::is_same_v<decltype(res), Result<Ok, nsresult>>);
+    EXPECT_TRUE(res.isOk());
+  }
+
+  // failure
+  {
+    auto res = ToResult(false);
+    static_assert(std::is_same_v<decltype(res), Result<Ok, nsresult>>);
+    EXPECT_TRUE(res.isErr());
+    EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+  }
+}
+
+TEST_F(DOM_Quota_ResultExtensions_ToResult, FromQMResult_Failure) {
+  // copy
+  {
+    const auto res = ToQMResult(NS_ERROR_FAILURE);
+    auto okOrErr = ToResult<QMResult>(res);
+    static_assert(std::is_same_v<decltype(okOrErr), OkOrErr>);
+    ASSERT_TRUE(okOrErr.isErr());
+    auto err = okOrErr.unwrapErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+    IncreaseExpectedStackId();
+
+    ASSERT_EQ(err.StackId(), ExpectedStackId());
+    ASSERT_EQ(err.FrameId(), 1u);
+    ASSERT_EQ(err.NSResult(), NS_ERROR_FAILURE);
+#else
+    ASSERT_EQ(err, NS_ERROR_FAILURE);
+#endif
+  }
+
+  // move
+  {
+    auto res = ToQMResult(NS_ERROR_FAILURE);
+    auto okOrErr = ToResult<QMResult>(std::move(res));
+    static_assert(std::is_same_v<decltype(okOrErr), OkOrErr>);
+    ASSERT_TRUE(okOrErr.isErr());
+    auto err = okOrErr.unwrapErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+    IncreaseExpectedStackId();
+
+    ASSERT_EQ(err.StackId(), ExpectedStackId());
+    ASSERT_EQ(err.FrameId(), 1u);
+    ASSERT_EQ(err.NSResult(), NS_ERROR_FAILURE);
+#else
+    ASSERT_EQ(err, NS_ERROR_FAILURE);
+#endif
+  }
+}
+
+TEST_F(DOM_Quota_ResultExtensions_ToResult, FromNSResult_Failure_Macro) {
+  auto okOrErr = QM_TO_RESULT(NS_ERROR_FAILURE);
+  static_assert(std::is_same_v<decltype(okOrErr), OkOrErr>);
+  ASSERT_TRUE(okOrErr.isErr());
+  auto err = okOrErr.unwrapErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(err.StackId(), ExpectedStackId());
+  ASSERT_EQ(err.FrameId(), 1u);
+  ASSERT_EQ(err.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(err, NS_ERROR_FAILURE);
+#endif
+}
+
+TEST_F(DOM_Quota_ResultExtensions_GenericErrorResult, ErrorPropagation) {
+  OkOrErr okOrErr1 = ToResult<QMResult>(ToQMResult(NS_ERROR_FAILURE));
+  const auto& err1 = okOrErr1.inspectErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  IncreaseExpectedStackId();
+
+  ASSERT_EQ(err1.StackId(), ExpectedStackId());
+  ASSERT_EQ(err1.FrameId(), 1u);
+  ASSERT_EQ(err1.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(err1, NS_ERROR_FAILURE);
+#endif
+
+  OkOrErr okOrErr2 = okOrErr1.propagateErr();
+  const auto& err2 = okOrErr2.inspectErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  ASSERT_EQ(err2.StackId(), ExpectedStackId());
+  ASSERT_EQ(err2.FrameId(), 2u);
+  ASSERT_EQ(err2.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(err2, NS_ERROR_FAILURE);
+#endif
+
+  OkOrErr okOrErr3 = okOrErr2.propagateErr();
+  const auto& err3 = okOrErr3.inspectErr();
+
+#ifdef QM_ERROR_STACKS_ENABLED
+  ASSERT_EQ(err3.StackId(), ExpectedStackId());
+  ASSERT_EQ(err3.FrameId(), 3u);
+  ASSERT_EQ(err3.NSResult(), NS_ERROR_FAILURE);
+#else
+  ASSERT_EQ(err3, NS_ERROR_FAILURE);
+#endif
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_NoInput)
+{
+  auto res = ToResultGet<int32_t>([](nsresult* aRv) -> int32_t {
+    *aRv = NS_OK;
+    return 42;
+  });
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_NoInput_Err)
+{
+  auto res = ToResultGet<int32_t>([](nsresult* aRv) -> int32_t {
+    *aRv = NS_ERROR_FAILURE;
+    return -1;
+  });
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_WithInput)
+{
+  auto res = ToResultGet<int32_t>(
+      [](int32_t aValue, nsresult* aRv) -> int32_t {
+        *aRv = NS_OK;
+        return aValue * 2;
+      },
+      42);
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 84);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_WithInput_Err)
+{
+  auto res = ToResultGet<int32_t>(
+      [](int32_t aValue, nsresult* aRv) -> int32_t {
+        *aRv = NS_ERROR_FAILURE;
+        return -1;
+      },
+      42);
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_NoInput_Macro_Typed)
+{
+  auto res = MOZ_TO_RESULT_GET_TYPED(int32_t, [](nsresult* aRv) -> int32_t {
+    *aRv = NS_OK;
+    return 42;
+  });
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 42);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_NoInput_Macro_Typed_Parens)
+{
+  auto res =
+      MOZ_TO_RESULT_GET_TYPED((std::pair<int32_t, int32_t>),
+                              [](nsresult* aRv) -> std::pair<int32_t, int32_t> {
+                                *aRv = NS_OK;
+                                return std::pair{42, 42};
+                              });
+
+  static_assert(std::is_same_v<decltype(res),
+                               Result<std::pair<int32_t, int32_t>, nsresult>>);
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), (std::pair{42, 42}));
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_NoInput_Err_Macro_Typed)
+{
+  auto res = MOZ_TO_RESULT_GET_TYPED(int32_t, [](nsresult* aRv) -> int32_t {
+    *aRv = NS_ERROR_FAILURE;
+    return -1;
+  });
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_WithInput_Macro_Typed)
+{
+  auto res = MOZ_TO_RESULT_GET_TYPED(
+      int32_t,
+      [](int32_t aValue, nsresult* aRv) -> int32_t {
+        *aRv = NS_OK;
+        return aValue * 2;
+      },
+      42);
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isOk());
+  EXPECT_EQ(res.unwrap(), 84);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultGet, Lambda_WithInput_Err_Macro_Typed)
+{
+  auto res = MOZ_TO_RESULT_GET_TYPED(
+      int32_t,
+      [](int32_t aValue, nsresult* aRv) -> int32_t {
+        *aRv = NS_ERROR_FAILURE;
+        return -1;
+      },
+      42);
+
+  static_assert(std::is_same_v<decltype(res), Result<int32_t, nsresult>>);
+
+  EXPECT_TRUE(res.isErr());
+  EXPECT_EQ(res.unwrapErr(), NS_ERROR_FAILURE);
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultInvoke, Lambda_NoInput_Complex)
+{
+  TestClass foo;
+
+  // success
+  {
+    auto valOrErr =
+        ToResultInvoke<std::pair<int, int>>([&foo](std::pair<int, int>* out) {
+          return foo.NonOverloadedNoInputComplex(out);
+        });
+    static_assert(std::is_same_v<decltype(valOrErr),
+                                 Result<std::pair<int, int>, nsresult>>);
+    ASSERT_TRUE(valOrErr.isOk());
+    ASSERT_EQ((std::pair{TestClass::kTestValue, TestClass::kTestValue}),
+              valOrErr.unwrap());
+  }
+
+  // failure
+  {
+    auto valOrErr =
+        ToResultInvoke<std::pair<int, int>>([&foo](std::pair<int, int>* out) {
+          return foo.NonOverloadedNoInputFailsComplex(out);
+        });
+    static_assert(std::is_same_v<decltype(valOrErr),
+                                 Result<std::pair<int, int>, nsresult>>);
+    ASSERT_TRUE(valOrErr.isErr());
+    ASSERT_EQ(NS_ERROR_FAILURE, valOrErr.unwrapErr());
+  }
+}
+
+TEST(DOM_Quota_ResultExtensions_ToResultInvoke,
+     Lambda_NoInput_Complex_Macro_Typed)
+{
+  TestClass foo;
+
+  // success
+  {
+    auto valOrErr = MOZ_TO_RESULT_INVOKE_TYPED(
+        (std::pair<int, int>), [&foo](std::pair<int, int>* out) {
+          return foo.NonOverloadedNoInputComplex(out);
+        });
+    static_assert(std::is_same_v<decltype(valOrErr),
+                                 Result<std::pair<int, int>, nsresult>>);
+    ASSERT_TRUE(valOrErr.isOk());
+    ASSERT_EQ((std::pair{TestClass::kTestValue, TestClass::kTestValue}),
+              valOrErr.unwrap());
+  }
+
+  // failure
+  {
+    auto valOrErr = MOZ_TO_RESULT_INVOKE_TYPED(
+        (std::pair<int, int>), [&foo](std::pair<int, int>* out) {
+          return foo.NonOverloadedNoInputFailsComplex(out);
+        });
+    static_assert(std::is_same_v<decltype(valOrErr),
+                                 Result<std::pair<int, int>, nsresult>>);
+    ASSERT_TRUE(valOrErr.isErr());
+    ASSERT_EQ(NS_ERROR_FAILURE, valOrErr.unwrapErr());
+  }
+}
diff --git a/dom/quota/test/gtest/TestScopedLogExtraInfo.cpp b/dom/quota/test/gtest/TestScopedLogExtraInfo.cpp
new file mode 100644
index 0000000000..00a3393844
--- /dev/null
+++ b/dom/quota/test/gtest/TestScopedLogExtraInfo.cpp
@@ -0,0 +1,65 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/ScopedLogExtraInfo.h"
+
+#include "gtest/gtest.h"
+
+using namespace mozilla::dom::quota;
+
+TEST(DOM_Quota_ScopedLogExtraInfo, AddAndRemove)
+{
+  static constexpr auto text = "foo"_ns;
+
+  {
+    const auto extraInfo =
+        ScopedLogExtraInfo{ScopedLogExtraInfo::kTagQuery, text};
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+    const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+
+    EXPECT_EQ(text, *extraInfoMap.at(ScopedLogExtraInfo::kTagQuery));
+#endif
+  }
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+
+  EXPECT_EQ(0u, extraInfoMap.count(ScopedLogExtraInfo::kTagQuery));
+#endif
+}
+
+TEST(DOM_Quota_ScopedLogExtraInfo, Nested)
+{
+  static constexpr auto text = "foo"_ns;
+  static constexpr auto nestedText = "bar"_ns;
+
+  {
+    const auto extraInfo =
+        ScopedLogExtraInfo{ScopedLogExtraInfo::kTagQuery, text};
+
+    {
+      const auto extraInfo =
+          ScopedLogExtraInfo{ScopedLogExtraInfo::kTagQuery, nestedText};
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+      const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+      EXPECT_EQ(nestedText, *extraInfoMap.at(ScopedLogExtraInfo::kTagQuery));
+#endif
+    }
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+    const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+    EXPECT_EQ(text, *extraInfoMap.at(ScopedLogExtraInfo::kTagQuery));
+#endif
+  }
+
+#ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
+  const auto& extraInfoMap = ScopedLogExtraInfo::GetExtraInfoMap();
+
+  EXPECT_EQ(0u, extraInfoMap.count(ScopedLogExtraInfo::kTagQuery));
+#endif
+}
diff --git a/dom/quota/test/gtest/TestUsageInfo.cpp b/dom/quota/test/gtest/TestUsageInfo.cpp
new file mode 100644
index 0000000000..124783b715
--- /dev/null
+++ b/dom/quota/test/gtest/TestUsageInfo.cpp
@@ -0,0 +1,136 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/quota/UsageInfo.h"
+
+#include "gtest/gtest.h"
+
+#include <cstdint>
+#include <memory>
+#include <ostream>
+#include <utility>
+#include "mozilla/Maybe.h"
+#include "mozilla/dom/quota/QuotaCommon.h"
+#include "mozilla/fallible.h"
+
+using namespace mozilla;
+using namespace mozilla::dom::quota;
+
+namespace {
+constexpr uint64_t kTestValue = 42;
+constexpr uint64_t kTestValueZero = 0;
+}  // namespace
+
+TEST(DOM_Quota_UsageInfo, DefaultConstructed)
+{
+  const UsageInfo usageInfo;
+  EXPECT_EQ(Nothing(), usageInfo.FileUsage());
+  EXPECT_EQ(Nothing(), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, FileOnly)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(kTestValue), usageInfo.FileUsage());
+  EXPECT_EQ(Some(kTestValue), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, DatabaseOnly)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += DatabaseUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Nothing(), usageInfo.FileUsage());
+  EXPECT_EQ(Some(kTestValue), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, FileOnly_Zero)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(kTestValueZero));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(kTestValueZero), usageInfo.FileUsage());
+  EXPECT_EQ(Some(kTestValueZero), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, DatabaseOnly_Zero)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += DatabaseUsageType(Some(kTestValueZero));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Nothing(), usageInfo.FileUsage());
+  EXPECT_EQ(Some(kTestValueZero), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, Both)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(kTestValue));
+    usageInfo += DatabaseUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(kTestValue), usageInfo.FileUsage());
+  EXPECT_EQ(Some(2 * kTestValue), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, Both_Zero)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(kTestValueZero));
+    usageInfo += DatabaseUsageType(Some(kTestValueZero));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(kTestValueZero), usageInfo.FileUsage());
+  EXPECT_EQ(Some(kTestValueZero), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, CapCombined)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(UINT64_MAX));
+    usageInfo += DatabaseUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(UINT64_MAX), usageInfo.FileUsage());
+  EXPECT_EQ(Some(UINT64_MAX), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, CapFileUsage)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += FileUsageType(Some(UINT64_MAX));
+    usageInfo += FileUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Some(UINT64_MAX), usageInfo.FileUsage());
+  EXPECT_EQ(Some(UINT64_MAX), usageInfo.TotalUsage());
+}
+
+TEST(DOM_Quota_UsageInfo, CapDatabaseUsage)
+{
+  const UsageInfo usageInfo = [] {
+    UsageInfo usageInfo;
+    usageInfo += DatabaseUsageType(Some(UINT64_MAX));
+    usageInfo += DatabaseUsageType(Some(kTestValue));
+    return usageInfo;
+  }();
+  EXPECT_EQ(Nothing(), usageInfo.FileUsage());
+  EXPECT_EQ(Some(UINT64_MAX), usageInfo.TotalUsage());
+}
diff --git a/dom/quota/test/gtest/moz.build b/dom/quota/test/gtest/moz.build
new file mode 100644
index 0000000000..30ca99b254
--- /dev/null
+++ b/dom/quota/test/gtest/moz.build
@@ -0,0 +1,44 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, you can obtain one at http://mozilla.org/MPL/2.0/.
+
+EXPORTS.mozilla.dom.quota += [
+    "QuotaTestChild.h",
+    "QuotaTestParent.h",
+]
+
+EXPORTS.mozilla.dom.quota.test += [
+    "QuotaManagerDependencyFixture.h",
+]
+
+UNIFIED_SOURCES = [
+    "Common.cpp",
+    "QuotaManagerDependencyFixture.cpp",
+    "TestCheckedUnsafePtr.cpp",
+    "TestClientUsageArray.cpp",
+    "TestEncryptedStream.cpp",
+    "TestFileOutputStream.cpp",
+    "TestFlatten.cpp",
+    "TestForwardDecls.cpp",
+    "TestPersistenceType.cpp",
+    "TestQMResult.cpp",
+    "TestQuotaCommon.cpp",
+    "TestQuotaManager.cpp",
+    "TestResultExtensions.cpp",
+    "TestScopedLogExtraInfo.cpp",
+    "TestUsageInfo.cpp",
+]
+
+IPDL_SOURCES += [
+    "PQuotaTest.ipdl",
+]
+
+include("/ipc/chromium/chromium-config.mozbuild")
+
+FINAL_LIBRARY = "xul-gtest"
+
+LOCAL_INCLUDES += [
+    "/dom/quota",
+]
diff --git a/dom/quota/test/mochitest/helpers.js b/dom/quota/test/mochitest/helpers.js
new file mode 100644
index 0000000000..4be2e131c2
--- /dev/null
+++ b/dom/quota/test/mochitest/helpers.js
@@ -0,0 +1,312 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../";
+
+var testGenerator;
+var testHarnessGenerator;
+var workerScriptPaths = [];
+
+loadScript("dom/quota/test/common/mochitest.js");
+
+function loadScript(path) {
+  const url = new URL(depth + path, window.location.href);
+  SpecialPowers.Services.scriptloader.loadSubScript(url.href, this);
+}
+
+function loadWorkerScript(path) {
+  const url = new URL(depth + path, window.location.href);
+  workerScriptPaths.push(url.href);
+}
+
+function* testHarnessSteps() {
+  function nextTestHarnessStep(val) {
+    testHarnessGenerator.next(val);
+  }
+
+  info("Enabling storage testing");
+
+  enableStorageTesting().then(nextTestHarnessStep);
+  yield undefined;
+
+  info("Pushing preferences");
+
+  SpecialPowers.pushPrefEnv(
+    {
+      set: [["dom.storageManager.prompt.testing", true]],
+    },
+    nextTestHarnessStep
+  );
+  yield undefined;
+
+  info("Clearing old databases");
+
+  clearAllDatabases(nextTestHarnessStep);
+  yield undefined;
+
+  info("Running test in given scopes");
+
+  if (workerScriptPaths.length) {
+    info("Running test in a worker");
+
+    let workerScriptBlob = new Blob(["(" + workerScript.toString() + ")();"], {
+      type: "text/javascript",
+    });
+    let workerScriptURL = URL.createObjectURL(workerScriptBlob);
+
+    let worker = new Worker(workerScriptURL);
+
+    worker.onerror = function(event) {
+      ok(false, "Worker had an error: " + event.message);
+      worker.terminate();
+      nextTestHarnessStep();
+    };
+
+    worker.onmessage = function(event) {
+      let message = event.data;
+      switch (message.op) {
+        case "ok":
+          ok(message.condition, message.name + " - " + message.diag);
+          break;
+
+        case "todo":
+          todo(message.condition, message.name, message.diag);
+          break;
+
+        case "info":
+          info(message.msg);
+          break;
+
+        case "ready":
+          worker.postMessage({ op: "load", files: workerScriptPaths });
+          break;
+
+        case "loaded":
+          worker.postMessage({ op: "start" });
+          break;
+
+        case "done":
+          ok(true, "Worker finished");
+          nextTestHarnessStep();
+          break;
+
+        case "clearAllDatabases":
+          clearAllDatabases(function() {
+            worker.postMessage({ op: "clearAllDatabasesDone" });
+          });
+          break;
+
+        default:
+          ok(
+            false,
+            "Received a bad message from worker: " + JSON.stringify(message)
+          );
+          nextTestHarnessStep();
+      }
+    };
+
+    URL.revokeObjectURL(workerScriptURL);
+
+    yield undefined;
+
+    worker.terminate();
+    worker = null;
+
+    clearAllDatabases(nextTestHarnessStep);
+    yield undefined;
+  }
+
+  info("Running test in main thread");
+
+  // Now run the test script in the main thread.
+  if (testSteps.constructor.name === "AsyncFunction") {
+    SimpleTest.registerCleanupFunction(async function() {
+      await requestFinished(clearAllDatabases());
+    });
+
+    add_task(testSteps);
+  } else {
+    testGenerator = testSteps();
+    testGenerator.next();
+
+    yield undefined;
+  }
+}
+
+if (!window.runTest) {
+  window.runTest = function() {
+    SimpleTest.waitForExplicitFinish();
+    testHarnessGenerator = testHarnessSteps();
+    testHarnessGenerator.next();
+  };
+}
+
+function finishTest() {
+  SimpleTest.executeSoon(function() {
+    clearAllDatabases(function() {
+      SimpleTest.finish();
+    });
+  });
+}
+
+function grabArgAndContinueHandler(arg) {
+  testGenerator.next(arg);
+}
+
+function continueToNextStep() {
+  SimpleTest.executeSoon(function() {
+    testGenerator.next();
+  });
+}
+
+function continueToNextStepSync() {
+  testGenerator.next();
+}
+
+function workerScript() {
+  "use strict";
+
+  self.testGenerator = null;
+
+  self.repr = function(_thing_) {
+    if (typeof _thing_ == "undefined") {
+      return "undefined";
+    }
+
+    let str;
+
+    try {
+      str = _thing_ + "";
+    } catch (e) {
+      return "[" + typeof _thing_ + "]";
+    }
+
+    if (typeof _thing_ == "function") {
+      str = str.replace(/^\s+/, "");
+      let idx = str.indexOf("{");
+      if (idx != -1) {
+        str = str.substr(0, idx) + "{...}";
+      }
+    }
+
+    return str;
+  };
+
+  self.ok = function(_condition_, _name_, _diag_) {
+    self.postMessage({
+      op: "ok",
+      condition: !!_condition_,
+      name: _name_,
+      diag: _diag_,
+    });
+  };
+
+  self.is = function(_a_, _b_, _name_) {
+    let pass = _a_ == _b_;
+    let diag = pass ? "" : "got " + repr(_a_) + ", expected " + repr(_b_);
+    ok(pass, _name_, diag);
+  };
+
+  self.isnot = function(_a_, _b_, _name_) {
+    let pass = _a_ != _b_;
+    let diag = pass ? "" : "didn't expect " + repr(_a_) + ", but got it";
+    ok(pass, _name_, diag);
+  };
+
+  self.todo = function(_condition_, _name_, _diag_) {
+    self.postMessage({
+      op: "todo",
+      condition: !!_condition_,
+      name: _name_,
+      diag: _diag_,
+    });
+  };
+
+  self.info = function(_msg_) {
+    self.postMessage({ op: "info", msg: _msg_ });
+  };
+
+  self.executeSoon = function(_fun_) {
+    var channel = new MessageChannel();
+    channel.port1.postMessage("");
+    channel.port2.onmessage = function(event) {
+      _fun_();
+    };
+  };
+
+  self.finishTest = function() {
+    self.postMessage({ op: "done" });
+  };
+
+  self.grabArgAndContinueHandler = function(_arg_) {
+    testGenerator.next(_arg_);
+  };
+
+  self.continueToNextStep = function() {
+    executeSoon(function() {
+      testGenerator.next();
+    });
+  };
+
+  self.continueToNextStepSync = function() {
+    testGenerator.next();
+  };
+
+  self._clearAllDatabasesCallback = undefined;
+  self.clearAllDatabases = function(_callback_) {
+    self._clearAllDatabasesCallback = _callback_;
+    self.postMessage({ op: "clearAllDatabases" });
+  };
+
+  self.onerror = function(_message_, _file_, _line_) {
+    ok(
+      false,
+      "Worker: uncaught exception [" +
+        _file_ +
+        ":" +
+        _line_ +
+        "]: '" +
+        _message_ +
+        "'"
+    );
+    self.finishTest();
+    self.close();
+    return true;
+  };
+
+  self.onmessage = function(_event_) {
+    let message = _event_.data;
+    switch (message.op) {
+      case "load":
+        info("Worker: loading " + JSON.stringify(message.files));
+        self.importScripts(message.files);
+        self.postMessage({ op: "loaded" });
+        break;
+
+      case "start":
+        executeSoon(function() {
+          info("Worker: starting tests");
+          testGenerator = testSteps();
+          testGenerator.next();
+        });
+        break;
+
+      case "clearAllDatabasesDone":
+        info("Worker: all databases are cleared");
+        if (self._clearAllDatabasesCallback) {
+          self._clearAllDatabasesCallback();
+        }
+        break;
+
+      default:
+        throw new Error(
+          "Received a bad message from parent: " + JSON.stringify(message)
+        );
+    }
+  };
+
+  self.postMessage({ op: "ready" });
+}
diff --git a/dom/quota/test/mochitest/mochitest.ini b/dom/quota/test/mochitest/mochitest.ini
new file mode 100644
index 0000000000..09cd6e66c8
--- /dev/null
+++ b/dom/quota/test/mochitest/mochitest.ini
@@ -0,0 +1,16 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+[DEFAULT]
+support-files =
+  helpers.js
+
+[test_simpledb.html]
+[test_storage_manager_persist_allow.html]
+fail-if = xorigin
+scheme=https
+[test_storage_manager_persist_deny.html]
+scheme=https
+[test_storage_manager_persisted.html]
+scheme=https
diff --git a/dom/quota/test/mochitest/test_simpledb.html b/dom/quota/test/mochitest/test_simpledb.html
new file mode 100644
index 0000000000..29ca8be65e
--- /dev/null
+++ b/dom/quota/test/mochitest/test_simpledb.html
@@ -0,0 +1,21 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+<head>
+  <title>SimpleDB Test</title>
+
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+
+  <script type="text/javascript" src="helpers.js"></script>
+  <script type="text/javascript">
+    loadScript("dom/quota/test/common/test_simpledb.js");
+  </script>
+
+</head>
+
+<body onload="runTest();"></body>
+
+</html>
diff --git a/dom/quota/test/mochitest/test_storage_manager_persist_allow.html b/dom/quota/test/mochitest/test_storage_manager_persist_allow.html
new file mode 100644
index 0000000000..8477630f21
--- /dev/null
+++ b/dom/quota/test/mochitest/test_storage_manager_persist_allow.html
@@ -0,0 +1,21 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+<head>
+  <title>Allow Persist Prompt for StorageManager</title>
+
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+
+  <script type="text/javascript" src="helpers.js"></script>
+  <script type="text/javascript">
+    loadScript("dom/quota/test/common/test_storage_manager_persist_allow.js");
+  </script>
+
+</head>
+
+<body onload="runTest();"></body>
+
+</html>
diff --git a/dom/quota/test/mochitest/test_storage_manager_persist_deny.html b/dom/quota/test/mochitest/test_storage_manager_persist_deny.html
new file mode 100644
index 0000000000..2b0fab4423
--- /dev/null
+++ b/dom/quota/test/mochitest/test_storage_manager_persist_deny.html
@@ -0,0 +1,21 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+<head>
+  <title>Deny Persist Prompt for StorageManager</title>
+
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+
+  <script type="text/javascript" src="helpers.js"></script>
+  <script type="text/javascript">
+    loadScript("dom/quota/test/common/test_storage_manager_persist_deny.js");
+  </script>
+
+</head>
+
+<body onload="runTest();"></body>
+
+</html>
diff --git a/dom/quota/test/mochitest/test_storage_manager_persisted.html b/dom/quota/test/mochitest/test_storage_manager_persisted.html
new file mode 100644
index 0000000000..6e03f33e2d
--- /dev/null
+++ b/dom/quota/test/mochitest/test_storage_manager_persisted.html
@@ -0,0 +1,24 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+<head>
+  <title>Storage Manager Persisted Test</title>
+
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+
+  <script type="text/javascript" src="helpers.js"></script>
+  <script type="text/javascript">
+    const path = "dom/quota/test/common/test_storage_manager_persisted.js";
+
+    loadScript(path);
+    loadWorkerScript(path);
+  </script>
+
+</head>
+
+<body onload="runTest();"></body>
+
+</html>
diff --git a/dom/quota/test/modules/content/.eslintrc.js b/dom/quota/test/modules/content/.eslintrc.js
new file mode 100644
index 0000000000..03499166b5
--- /dev/null
+++ b/dom/quota/test/modules/content/.eslintrc.js
@@ -0,0 +1,22 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+"use strict";
+
+module.exports = {
+  overrides: [
+    {
+      files: [
+        "Assert.js",
+        "ModuleLoader.js",
+        "StorageUtils.js",
+        "WorkerDriver.js",
+      ],
+      parserOptions: {
+        sourceType: "module",
+      },
+    },
+  ],
+};
diff --git a/dom/quota/test/modules/content/Assert.js b/dom/quota/test/modules/content/Assert.js
new file mode 100644
index 0000000000..e2c8df19c8
--- /dev/null
+++ b/dom/quota/test/modules/content/Assert.js
@@ -0,0 +1,10 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// Just a wrapper around SimpleTest related functions for now.
+export const Assert = {
+  ok,
+  equal: is,
+};
diff --git a/dom/quota/test/modules/content/ModuleLoader.js b/dom/quota/test/modules/content/ModuleLoader.js
new file mode 100644
index 0000000000..a47061f751
--- /dev/null
+++ b/dom/quota/test/modules/content/ModuleLoader.js
@@ -0,0 +1,61 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+export function ModuleLoader(base, depth, proto) {
+  const modules = {};
+
+  const principal = SpecialPowers.wrap(document).nodePrincipal;
+
+  const sharedGlobalSandbox = SpecialPowers.Cu.Sandbox(principal, {
+    invisibleToDebugger: true,
+    sandboxName: "FS Module Loader",
+    sandboxPrototype: proto,
+    wantComponents: false,
+    wantGlobalProperties: [],
+    wantXrays: false,
+  });
+
+  const require = async function(id) {
+    if (modules[id]) {
+      return modules[id].exported_symbols;
+    }
+
+    const url = new URL(depth + id, base);
+
+    const module = Object.create(null, {
+      exported_symbols: {
+        configurable: false,
+        enumerable: true,
+        value: Object.create(null),
+        writable: true,
+      },
+    });
+
+    modules[id] = module;
+
+    const properties = {
+      require_module: require,
+      exported_symbols: module.exported_symbols,
+    };
+
+    // Create a new object in this sandbox, that will be used as the scope
+    // object for this particular module.
+    const sandbox = sharedGlobalSandbox.Object();
+    Object.assign(sandbox, properties);
+
+    SpecialPowers.Services.scriptloader.loadSubScript(url.href, sandbox);
+
+    return module.exported_symbols;
+  };
+
+  const returnObj = {
+    require: {
+      enumerable: true,
+      value: require,
+    },
+  };
+
+  return Object.create(null, returnObj);
+}
diff --git a/dom/quota/test/modules/content/StorageUtils.js b/dom/quota/test/modules/content/StorageUtils.js
new file mode 100644
index 0000000000..b29f7d9c26
--- /dev/null
+++ b/dom/quota/test/modules/content/StorageUtils.js
@@ -0,0 +1,48 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+class RequestError extends Error {
+  constructor(resultCode, resultName) {
+    super(`Request failed (code: ${resultCode}, name: ${resultName})`);
+    this.name = "RequestError";
+    this.resultCode = resultCode;
+    this.resultName = resultName;
+  }
+}
+
+export async function setStoragePrefs(optionalPrefsToSet) {
+  const prefsToSet = [
+    // Not needed right now, but might be needed in future.
+    // ["dom.quotaManager.testing", true],
+  ];
+
+  if (SpecialPowers.Services.appinfo.OS === "WINNT") {
+    prefsToSet.push(["dom.quotaManager.useDOSDevicePathSyntax", true]);
+  }
+
+  if (optionalPrefsToSet) {
+    prefsToSet.push(...optionalPrefsToSet);
+  }
+
+  await SpecialPowers.pushPrefEnv({ set: prefsToSet });
+}
+
+export async function clearStoragesForOrigin(principal) {
+  const request = SpecialPowers.Services.qms.clearStoragesForPrincipal(
+    principal
+  );
+
+  await new Promise(function(resolve) {
+    request.callback = SpecialPowers.wrapCallback(function() {
+      resolve();
+    });
+  });
+
+  if (request.resultCode != SpecialPowers.Cr.NS_OK) {
+    throw new RequestError(request.resultCode, request.resultName);
+  }
+
+  return request.result;
+}
diff --git a/dom/quota/test/modules/content/WorkerDriver.js b/dom/quota/test/modules/content/WorkerDriver.js
new file mode 100644
index 0000000000..365d00f363
--- /dev/null
+++ b/dom/quota/test/modules/content/WorkerDriver.js
@@ -0,0 +1,53 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+export async function runTestInWorker(script, base, listener) {
+  return new Promise(function(resolve) {
+    const globalHeadUrl = new URL(
+      "/tests/dom/quota/test/modules/worker/head.js",
+      base
+    );
+
+    const worker = new Worker(globalHeadUrl.href);
+
+    worker.onmessage = function(event) {
+      const data = event.data;
+
+      switch (data.op) {
+        case "ok":
+          listener.onOk(data.value, data.message);
+          break;
+
+        case "is":
+          listener.onIs(data.a, data.b, data.message);
+          break;
+
+        case "info":
+          listener.onInfo(data.message);
+          break;
+
+        case "finish":
+          resolve();
+          break;
+
+        case "failure":
+          listener.onOk(false, "Worker had a failure: " + data.message);
+          resolve();
+          break;
+      }
+    };
+
+    worker.onerror = function(event) {
+      listener.onOk(false, "Worker had an error: " + event.data);
+      resolve();
+    };
+
+    const scriptUrl = new URL(script, base);
+
+    const localHeadUrl = new URL("head.js", scriptUrl);
+
+    worker.postMessage([localHeadUrl.href, scriptUrl.href]);
+  });
+}
diff --git a/dom/quota/test/modules/content/worker/.eslintrc.js b/dom/quota/test/modules/content/worker/.eslintrc.js
new file mode 100644
index 0000000000..470c23b2fa
--- /dev/null
+++ b/dom/quota/test/modules/content/worker/.eslintrc.js
@@ -0,0 +1,21 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+"use strict";
+
+module.exports = {
+  env: {
+    worker: true,
+  },
+
+  overrides: [
+    {
+      files: ["Assert.js", "ModuleLoader.js"],
+      parserOptions: {
+        sourceType: "script",
+      },
+    },
+  ],
+};
diff --git a/dom/quota/test/modules/content/worker/Assert.js b/dom/quota/test/modules/content/worker/Assert.js
new file mode 100644
index 0000000000..7c7e2683ea
--- /dev/null
+++ b/dom/quota/test/modules/content/worker/Assert.js
@@ -0,0 +1,22 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const Assert = {
+  ok(value, message) {
+    postMessage({
+      op: "ok",
+      value: !!value,
+      message,
+    });
+  },
+  equal(a, b, message) {
+    postMessage({
+      op: "is",
+      a,
+      b,
+      message,
+    });
+  },
+};
diff --git a/dom/quota/test/modules/content/worker/ModuleLoader.js b/dom/quota/test/modules/content/worker/ModuleLoader.js
new file mode 100644
index 0000000000..23ee7c06df
--- /dev/null
+++ b/dom/quota/test/modules/content/worker/ModuleLoader.js
@@ -0,0 +1,52 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function ModuleLoader(base, depth) {
+  const modules = {};
+
+  const require = async function(id) {
+    if (modules[id]) {
+      return modules[id].exported_symbols;
+    }
+
+    const url = new URL(depth + id, base);
+
+    const module = Object.create(null, {
+      exported_symbols: {
+        configurable: false,
+        enumerable: true,
+        value: Object.create(null),
+        writable: true,
+      },
+    });
+
+    modules[id] = module;
+
+    const xhr = new XMLHttpRequest();
+    xhr.open("GET", url.href, false);
+    xhr.responseType = "text";
+    xhr.send();
+
+    let source = xhr.responseText;
+
+    let code = new Function(
+      "require_module",
+      "exported_symbols",
+      `eval(arguments[2] + "\\n//# sourceURL=" + arguments[3] + "\\n")`
+    );
+    code(require, module.exported_symbols, source, url.href);
+
+    return module.exported_symbols;
+  };
+
+  const returnObj = {
+    require: {
+      enumerable: true,
+      value: require,
+    },
+  };
+
+  return Object.create(null, returnObj);
+}
diff --git a/dom/quota/test/modules/content/worker/head.js b/dom/quota/test/modules/content/worker/head.js
new file mode 100644
index 0000000000..58d4591e47
--- /dev/null
+++ b/dom/quota/test/modules/content/worker/head.js
@@ -0,0 +1,55 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const Cr = {
+  NS_ERROR_NOT_IMPLEMENTED: 2147500033,
+};
+
+function add_task(func) {
+  if (!add_task.tasks) {
+    add_task.tasks = [];
+    add_task.index = 0;
+  }
+
+  add_task.tasks.push(func);
+}
+
+addEventListener("message", async function onMessage(event) {
+  function info(message) {
+    postMessage({ op: "info", message });
+  }
+
+  function executeSoon(callback) {
+    const channel = new MessageChannel();
+    channel.port1.postMessage("");
+    channel.port2.onmessage = function() {
+      callback();
+    };
+  }
+
+  function runNextTest() {
+    if (add_task.index < add_task.tasks.length) {
+      const task = add_task.tasks[add_task.index++];
+      info("add_task | Entering test " + task.name);
+      task()
+        .then(function() {
+          executeSoon(runNextTest);
+          info("add_task | Leaving test " + task.name);
+        })
+        .catch(function(ex) {
+          postMessage({ op: "failure", message: "" + ex });
+        });
+    } else {
+      postMessage({ op: "finish" });
+    }
+  }
+
+  removeEventListener("message", onMessage);
+
+  const data = event.data;
+  importScripts(...data);
+
+  executeSoon(runNextTest);
+});
diff --git a/dom/quota/test/modules/system/ModuleLoader.sys.mjs b/dom/quota/test/modules/system/ModuleLoader.sys.mjs
new file mode 100644
index 0000000000..7bddfd2760
--- /dev/null
+++ b/dom/quota/test/modules/system/ModuleLoader.sys.mjs
@@ -0,0 +1,63 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+export function ModuleLoader(base, depth, proto) {
+  const modules = {};
+
+  const principal = Cc["@mozilla.org/systemprincipal;1"].createInstance(
+    Ci.nsIPrincipal
+  );
+
+  const sharedGlobalsandbox = Cu.Sandbox(principal, {
+    invisibleToDebugger: true,
+    sandboxName: "FS Module Loader",
+    sandboxPrototype: proto,
+    wantComponents: false,
+    wantGlobalProperties: [],
+    wantXrays: false,
+  });
+
+  const require = async function(id) {
+    if (modules[id]) {
+      return modules[id].exported_symbols;
+    }
+
+    const url = new URL(depth + id, base);
+
+    const module = Object.create(null, {
+      exported_symbols: {
+        configurable: false,
+        enumerable: true,
+        value: Object.create(null),
+        writable: true,
+      },
+    });
+
+    modules[id] = module;
+
+    const properties = {
+      require_module: require,
+      exported_symbols: module.exported_symbols,
+    };
+
+    // Create a new object in this sandbox, that will be used as the scope
+    // object for this particular module.
+    const sandbox = sharedGlobalsandbox.Object();
+    Object.assign(sandbox, properties);
+
+    Services.scriptloader.loadSubScript(url.href, sandbox);
+
+    return module.exported_symbols;
+  };
+
+  const returnObj = {
+    require: {
+      enumerable: true,
+      value: require,
+    },
+  };
+
+  return Object.create(null, returnObj);
+}
diff --git a/dom/quota/test/modules/system/StorageUtils.sys.mjs b/dom/quota/test/modules/system/StorageUtils.sys.mjs
new file mode 100644
index 0000000000..bda40a4747
--- /dev/null
+++ b/dom/quota/test/modules/system/StorageUtils.sys.mjs
@@ -0,0 +1,65 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+class RequestError extends Error {
+  constructor(resultCode, resultName) {
+    super(`Request failed (code: ${resultCode}, name: ${resultName})`);
+    this.name = "RequestError";
+    this.resultCode = resultCode;
+    this.resultName = resultName;
+  }
+}
+
+export function setStoragePrefs(optionalPrefsToSet) {
+  const prefsToSet = [["dom.quotaManager.testing", true]];
+
+  if (Services.appinfo.OS === "WINNT") {
+    prefsToSet.push(["dom.quotaManager.useDOSDevicePathSyntax", true]);
+  }
+
+  if (optionalPrefsToSet) {
+    prefsToSet.push(...optionalPrefsToSet);
+  }
+
+  for (const pref of prefsToSet) {
+    Services.prefs.setBoolPref(pref[0], pref[1]);
+  }
+}
+
+export function clearStoragePrefs(optionalPrefsToClear) {
+  const prefsToClear = [
+    "dom.quotaManager.testing",
+    "dom.simpleDB.enabled",
+    "dom.storageManager.enabled",
+  ];
+
+  if (Services.appinfo.OS === "WINNT") {
+    prefsToClear.push("dom.quotaManager.useDOSDevicePathSyntax");
+  }
+
+  if (optionalPrefsToClear) {
+    prefsToClear.push(...optionalPrefsToClear);
+  }
+
+  for (const pref of prefsToClear) {
+    Services.prefs.clearUserPref(pref);
+  }
+}
+
+export async function clearStoragesForOrigin(principal) {
+  const request = Services.qms.clearStoragesForPrincipal(principal);
+
+  await new Promise(function(resolve) {
+    request.callback = function() {
+      resolve();
+    };
+  });
+
+  if (request.resultCode != Cr.NS_OK) {
+    throw new RequestError(request.resultCode, request.resultName);
+  }
+
+  return request.result;
+}
diff --git a/dom/quota/test/modules/system/WorkerDriver.sys.mjs b/dom/quota/test/modules/system/WorkerDriver.sys.mjs
new file mode 100644
index 0000000000..c03a94cf56
--- /dev/null
+++ b/dom/quota/test/modules/system/WorkerDriver.sys.mjs
@@ -0,0 +1,52 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+export async function runTestInWorker(script, base, listener) {
+  return new Promise(function(resolve) {
+    const globalHeadUrl = new URL(
+      "resource://testing-common/dom/quota/test/modules/worker/head.js"
+    );
+
+    const worker = new Worker(globalHeadUrl.href);
+
+    worker.onmessage = function(event) {
+      const data = event.data;
+
+      switch (data.op) {
+        case "ok":
+          listener.onOk(data.value, data.message);
+          break;
+
+        case "is":
+          listener.onIs(data.a, data.b, data.message);
+          break;
+
+        case "info":
+          listener.onInfo(data.message);
+          break;
+
+        case "finish":
+          resolve();
+          break;
+
+        case "failure":
+          listener.onOk(false, "Worker had a failure: " + data.message);
+          resolve();
+          break;
+      }
+    };
+
+    worker.onerror = function(event) {
+      listener.onOk(false, "Worker had an error: " + event.data);
+      resolve();
+    };
+
+    const scriptUrl = new URL(script, base);
+
+    const localHeadUrl = new URL("head.js", scriptUrl);
+
+    worker.postMessage([localHeadUrl.href, scriptUrl.href]);
+  });
+}
diff --git a/dom/quota/test/modules/system/worker/.eslintrc.js b/dom/quota/test/modules/system/worker/.eslintrc.js
new file mode 100644
index 0000000000..505e079c57
--- /dev/null
+++ b/dom/quota/test/modules/system/worker/.eslintrc.js
@@ -0,0 +1,21 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+"use strict";
+
+module.exports = {
+  env: {
+    worker: true,
+  },
+
+  overrides: [
+    {
+      files: ["head.js"],
+      env: {
+        worker: true,
+      },
+    },
+  ],
+};
diff --git a/dom/quota/test/modules/system/worker/Assert.js b/dom/quota/test/modules/system/worker/Assert.js
new file mode 100644
index 0000000000..7c7e2683ea
--- /dev/null
+++ b/dom/quota/test/modules/system/worker/Assert.js
@@ -0,0 +1,22 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const Assert = {
+  ok(value, message) {
+    postMessage({
+      op: "ok",
+      value: !!value,
+      message,
+    });
+  },
+  equal(a, b, message) {
+    postMessage({
+      op: "is",
+      a,
+      b,
+      message,
+    });
+  },
+};
diff --git a/dom/quota/test/modules/system/worker/ModuleLoader.js b/dom/quota/test/modules/system/worker/ModuleLoader.js
new file mode 100644
index 0000000000..6de1fbc299
--- /dev/null
+++ b/dom/quota/test/modules/system/worker/ModuleLoader.js
@@ -0,0 +1,52 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function ModuleLoader(base, depth, proto) {
+  const modules = {};
+
+  const require = async function(id) {
+    if (modules[id]) {
+      return modules[id].exported_symbols;
+    }
+
+    const url = new URL(depth + id, base);
+
+    const module = Object.create(null, {
+      exported_symbols: {
+        configurable: false,
+        enumerable: true,
+        value: Object.create(null),
+        writable: true,
+      },
+    });
+
+    modules[id] = module;
+
+    const xhr = new XMLHttpRequest();
+    xhr.open("GET", url.href, false);
+    xhr.responseType = "text";
+    xhr.send();
+
+    let source = xhr.responseText;
+
+    let code = new Function(
+      "require_module",
+      "exported_symbols",
+      `eval(arguments[2] + "\\n//# sourceURL=" + arguments[3] + "\\n")`
+    );
+    code(require, module.exported_symbols, source, url.href);
+
+    return module.exported_symbols;
+  };
+
+  const returnObj = {
+    require: {
+      enumerable: true,
+      value: require,
+    },
+  };
+
+  return Object.create(null, returnObj);
+}
diff --git a/dom/quota/test/modules/system/worker/head.js b/dom/quota/test/modules/system/worker/head.js
new file mode 100644
index 0000000000..1308508918
--- /dev/null
+++ b/dom/quota/test/modules/system/worker/head.js
@@ -0,0 +1,56 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// eslint-disable-next-line mozilla/no-define-cc-etc
+const Cr = {
+  NS_ERROR_NOT_IMPLEMENTED: 2147500033,
+};
+
+function add_task(func) {
+  if (!add_task.tasks) {
+    add_task.tasks = [];
+    add_task.index = 0;
+  }
+
+  add_task.tasks.push(func);
+}
+
+addEventListener("message", async function onMessage(event) {
+  function info(message) {
+    postMessage({ op: "info", message });
+  }
+
+  function executeSoon(callback) {
+    const channel = new MessageChannel();
+    channel.port1.postMessage("");
+    channel.port2.onmessage = function() {
+      callback();
+    };
+  }
+
+  function runNextTest() {
+    if (add_task.index < add_task.tasks.length) {
+      const task = add_task.tasks[add_task.index++];
+      info("add_task | Entering test " + task.name);
+      task()
+        .then(function() {
+          executeSoon(runNextTest);
+          info("add_task | Leaving test " + task.name);
+        })
+        .catch(function(ex) {
+          postMessage({ op: "failure", message: "" + ex });
+        });
+    } else {
+      postMessage({ op: "finish" });
+    }
+  }
+
+  removeEventListener("message", onMessage);
+
+  const data = event.data;
+  importScripts(...data);
+
+  executeSoon(runNextTest);
+});
diff --git a/dom/quota/test/moz.build b/dom/quota/test/moz.build
new file mode 100644
index 0000000000..bab65f643e
--- /dev/null
+++ b/dom/quota/test/moz.build
@@ -0,0 +1,76 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+TEST_DIRS += ["gtest"]
+
+BROWSER_CHROME_MANIFESTS += ["browser/browser.ini"]
+
+MOCHITEST_MANIFESTS += ["mochitest/mochitest.ini"]
+
+XPCSHELL_TESTS_MANIFESTS += [
+    "xpcshell/caching/xpcshell.ini",
+    "xpcshell/telemetry/xpcshell.ini",
+    "xpcshell/upgrades/xpcshell.ini",
+    "xpcshell/xpcshell.ini",
+]
+
+TEST_HARNESS_FILES.testing.mochitest.browser.dom.quota.test.common += [
+    "common/browser.js",
+    "common/content.js",
+    "common/file.js",
+    "common/global.js",
+    "common/nestedtest.js",
+    "common/system.js",
+]
+
+TEST_HARNESS_FILES.testing.mochitest.tests.dom.quota.test.common += [
+    "common/content.js",
+    "common/file.js",
+    "common/global.js",
+    "common/mochitest.js",
+    "common/test_simpledb.js",
+    "common/test_storage_manager_persist_allow.js",
+    "common/test_storage_manager_persist_deny.js",
+    "common/test_storage_manager_persisted.js",
+]
+
+TEST_HARNESS_FILES.testing.mochitest.tests.dom.quota.test.modules += [
+    "modules/content/Assert.js",
+    "modules/content/ModuleLoader.js",
+    "modules/content/StorageUtils.js",
+    "modules/content/WorkerDriver.js",
+]
+
+TEST_HARNESS_FILES.testing.mochitest.tests.dom.quota.test.modules.worker += [
+    "modules/content/worker/Assert.js",
+    "modules/content/worker/head.js",
+    "modules/content/worker/ModuleLoader.js",
+]
+
+TEST_HARNESS_FILES.xpcshell.dom.quota.test.common += [
+    "common/file.js",
+    "common/global.js",
+    "common/system.js",
+    "common/test_simpledb.js",
+    "common/xpcshell.js",
+]
+
+TEST_HARNESS_FILES.xpcshell.dom.quota.test.xpcshell.common += [
+    "xpcshell/common/head.js",
+    "xpcshell/common/utils.js",
+]
+
+TESTING_JS_MODULES.dom.quota.test.modules += [
+    "modules/system/ModuleLoader.sys.mjs",
+    "modules/system/StorageUtils.sys.mjs",
+    "modules/system/WorkerDriver.sys.mjs",
+]
+
+TESTING_JS_MODULES.dom.quota.test.modules.worker += [
+    "modules/system/worker/Assert.js",
+    "modules/system/worker/head.js",
+    "modules/system/worker/ModuleLoader.js",
+]
diff --git a/dom/quota/test/xpcshell/basics_profile.zip b/dom/quota/test/xpcshell/basics_profile.zip
new file mode 100644
index 0000000000..bbdb0f50cf
--- /dev/null
+++ b/dom/quota/test/xpcshell/basics_profile.zip
diff --git a/dom/quota/test/xpcshell/caching/groupMismatch_profile.zip b/dom/quota/test/xpcshell/caching/groupMismatch_profile.zip
new file mode 100644
index 0000000000..8124e589de
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/groupMismatch_profile.zip
diff --git a/dom/quota/test/xpcshell/caching/head.js b/dom/quota/test/xpcshell/caching/head.js
new file mode 100644
index 0000000000..5c36d82ca6
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/head.js
@@ -0,0 +1,14 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../../";
+
+loadScript("dom/quota/test/xpcshell/common/head.js");
+
+function loadScript(path) {
+  let uri = Services.io.newFileURI(do_get_file(depth + path));
+  Services.scriptloader.loadSubScript(uri.spec);
+}
diff --git a/dom/quota/test/xpcshell/caching/make_unsetLastAccessTime.js b/dom/quota/test/xpcshell/caching/make_unsetLastAccessTime.js
new file mode 100644
index 0000000000..9be377e4f3
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/make_unsetLastAccessTime.js
@@ -0,0 +1,25 @@
+/*
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+*/
+
+async function testSteps() {
+  const originDirPath = "storage/default/https+++foo.example.com";
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Creating an empty origin directory");
+
+  let originDir = getRelativeFile(originDirPath);
+  originDir.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  // The metadata file should be now restored.
+}
diff --git a/dom/quota/test/xpcshell/caching/removedOrigin_profile.zip b/dom/quota/test/xpcshell/caching/removedOrigin_profile.zip
new file mode 100644
index 0000000000..a5ccc05aa9
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/removedOrigin_profile.zip
diff --git a/dom/quota/test/xpcshell/caching/test_groupMismatch.js b/dom/quota/test/xpcshell/caching/test_groupMismatch.js
new file mode 100644
index 0000000000..3f8e843798
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/test_groupMismatch.js
@@ -0,0 +1,45 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that the group loaded from the origin table
+ * gets updated (if necessary) before quota initialization for the given origin.
+ */
+
+async function testSteps() {
+  const principal = getPrincipal("https://foo.bar.mozilla-iot.org");
+  const originUsage = 100;
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains one initialized origin directory with simple database
+  // data, a script for origin initialization and the storage database:
+  // - storage/default/https+++foo.bar.mozilla-iot.org
+  // - create_db.js
+  // - storage.sqlite
+  // The file create_db.js in the package was run locally, specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  //   mach xpcshell-test --interactive dom/quota/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Manually change the group and accessed values in the origin table in
+  //    storage.sqlite by running this SQL statement:
+  //    UPDATE origin SET group_ = 'mozilla-iot.org', accessed = 0
+  // 2. Manually change the group in .metadata-v2 from "bar.mozilla-iot.org" to
+  //    "mozilla-iot.org".
+  // 3. Remove the folder "storage/temporary".
+  // 4. Remove the file "storage/ls-archive.sqlite".
+  installPackage("groupMismatch_profile");
+
+  request = getOriginUsage(principal, /* fromMemory */ true);
+  await requestFinished(request);
+
+  is(request.result.usage, originUsage, "Correct origin usage");
+}
diff --git a/dom/quota/test/xpcshell/caching/test_removedOrigin.js b/dom/quota/test/xpcshell/caching/test_removedOrigin.js
new file mode 100644
index 0000000000..8b5702ad9c
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/test_removedOrigin.js
@@ -0,0 +1,61 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * Verify that temporary storage initialization will notice a removed origin
+ * that the cache has data for and which indicates the origin was accessed
+ * during the last run. Currently, we expect LoadQuotaFromCache to fail because
+ * of this inconsistency and to fall back to full initialization.
+ */
+
+async function testSteps() {
+  const principal = getPrincipal("http://example.com");
+  const originUsage = 0;
+
+  info("Setting pref");
+
+  // The packaged profile will have a different build ID and we would treat the
+  // cache as invalid if we didn't bypass this check.
+  Services.prefs.setBoolPref("dom.quotaManager.caching.checkBuildId", false);
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains empty default storage, a script for origin
+  // initialization and the storage database:
+  // - storage/default
+  // - create_db.js
+  // - storage.sqlite
+  // The file create_db.js in the package was run locally, specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  //   mach xpcshell-test --interactive dom/quota/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/default/http+++example.com".
+  // 2. Remove the folder "storage/temporary".
+  // 3. Remove the file "storage/ls-archive.sqlite".
+  installPackage("removedOrigin_profile");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Getting origin usage");
+
+  request = getOriginUsage(principal, /* fromMemory */ true);
+  await requestFinished(request);
+
+  is(request.result.usage, originUsage, "Correct origin usage");
+}
diff --git a/dom/quota/test/xpcshell/caching/test_unsetLastAccessTime.js b/dom/quota/test/xpcshell/caching/test_unsetLastAccessTime.js
new file mode 100644
index 0000000000..5abe76eade
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/test_unsetLastAccessTime.js
@@ -0,0 +1,46 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const principal = getPrincipal("https://foo.example.com/");
+
+  info("Setting pref");
+
+  // The packaged profile will have a different build ID and we would treat the
+  // cache as invalid if we didn't bypass this check.
+  Services.prefs.setBoolPref("dom.quotaManager.caching.checkBuildId", false);
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains one initialized origin directory and the storage
+  // database:
+  // - storage/default/https+++foo.example.com
+  // - storage.sqlite
+  // The file make_unsetLastAccessTime.js was run locally, specifically it was
+  // temporarily enabled in xpcshell.ini and then executed:
+  // mach test --interactive dom/quota/test/xpcshell/caching/make_unsetLastAccessTime.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/temporary".
+  // 2. Remove the file "storage/ls-archive.sqlite".
+  installPackage("unsetLastAccessTime_profile");
+
+  info("Getting full origin metadata");
+
+  request = getFullOriginMetadata("default", principal);
+  await requestFinished(request);
+
+  info("Verifying last access time");
+
+  ok(
+    BigInt(request.result.lastAccessTime) != INT64_MIN,
+    "Correct last access time"
+  );
+}
diff --git a/dom/quota/test/xpcshell/caching/unsetLastAccessTime_profile.zip b/dom/quota/test/xpcshell/caching/unsetLastAccessTime_profile.zip
new file mode 100644
index 0000000000..2b14ca7276
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/unsetLastAccessTime_profile.zip
diff --git a/dom/quota/test/xpcshell/caching/xpcshell.ini b/dom/quota/test/xpcshell/caching/xpcshell.ini
new file mode 100644
index 0000000000..d08f15c0a8
--- /dev/null
+++ b/dom/quota/test/xpcshell/caching/xpcshell.ini
@@ -0,0 +1,17 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+[DEFAULT]
+head = head.js
+support-files =
+  groupMismatch_profile.zip
+  removedOrigin_profile.zip
+
+[make_unsetLastAccessTime.js]
+skip-if = true # Only used for recreating unsetLastAccessTime_profile.zip
+[test_groupMismatch.js]
+[test_removedOrigin.js]
+[test_unsetLastAccessTime.js]
+support-files =
+  unsetLastAccessTime_profile.zip
diff --git a/dom/quota/test/xpcshell/clearStoragesForPrincipal_profile.zip b/dom/quota/test/xpcshell/clearStoragesForPrincipal_profile.zip
new file mode 100644
index 0000000000..7d7985ddd0
--- /dev/null
+++ b/dom/quota/test/xpcshell/clearStoragesForPrincipal_profile.zip
diff --git a/dom/quota/test/xpcshell/common/head.js b/dom/quota/test/xpcshell/common/head.js
new file mode 100644
index 0000000000..3471b56de7
--- /dev/null
+++ b/dom/quota/test/xpcshell/common/head.js
@@ -0,0 +1,629 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const NS_OK = Cr.NS_OK;
+const NS_ERROR_FAILURE = Cr.NS_ERROR_FAILURE;
+const NS_ERROR_UNEXPECTED = Cr.NS_ERROR_UNEXPECTED;
+const NS_ERROR_FILE_NO_DEVICE_SPACE = Cr.NS_ERROR_FILE_NO_DEVICE_SPACE;
+
+const loggingEnabled = false;
+
+var testGenerator;
+
+loadScript("dom/quota/test/common/xpcshell.js");
+
+function log(msg) {
+  if (loggingEnabled) {
+    info(msg);
+  }
+}
+
+function is(a, b, msg) {
+  Assert.equal(a, b, msg);
+}
+
+function ok(cond, msg) {
+  Assert.ok(!!cond, msg);
+}
+
+function todo(cond, msg) {
+  todo_check_true(cond);
+}
+
+function run_test() {
+  runTest();
+}
+
+if (!this.runTest) {
+  this.runTest = function() {
+    do_get_profile();
+
+    enableStorageTesting();
+    enableTesting();
+
+    Cu.importGlobalProperties(["indexedDB", "File", "Blob", "FileReader"]);
+
+    // In order to support converting tests to using async functions from using
+    // generator functions, we detect async functions by checking the name of
+    // function's constructor.
+    Assert.ok(
+      typeof testSteps === "function",
+      "There should be a testSteps function"
+    );
+    if (testSteps.constructor.name === "AsyncFunction") {
+      // Do run our existing cleanup function that would normally be called by
+      // the generator's call to finishTest().
+      registerCleanupFunction(function() {
+        resetStorageTesting();
+        resetTesting();
+      });
+
+      add_task(testSteps);
+
+      // Since we defined run_test, we must invoke run_next_test() to start the
+      // async test.
+      run_next_test();
+    } else {
+      Assert.ok(
+        testSteps.constructor.name === "GeneratorFunction",
+        "Unsupported function type"
+      );
+
+      do_test_pending();
+
+      testGenerator = testSteps();
+      testGenerator.next();
+    }
+  };
+}
+
+function finishTest() {
+  resetStorageTesting();
+  resetTesting();
+
+  executeSoon(function() {
+    do_test_finished();
+  });
+}
+
+function grabArgAndContinueHandler(arg) {
+  testGenerator.next(arg);
+}
+
+function continueToNextStep() {
+  executeSoon(function() {
+    testGenerator.next();
+  });
+}
+
+function continueToNextStepSync() {
+  testGenerator.next();
+}
+
+function enableTesting() {
+  SpecialPowers.setBoolPref(
+    "dom.storage.enable_unsupported_legacy_implementation",
+    false
+  );
+}
+
+function resetTesting() {
+  SpecialPowers.clearUserPref(
+    "dom.storage.enable_unsupported_legacy_implementation"
+  );
+}
+
+function setGlobalLimit(globalLimit) {
+  SpecialPowers.setIntPref(
+    "dom.quotaManager.temporaryStorage.fixedLimit",
+    globalLimit
+  );
+}
+
+function resetGlobalLimit() {
+  SpecialPowers.clearUserPref("dom.quotaManager.temporaryStorage.fixedLimit");
+}
+
+function storageInitialized(callback) {
+  let request = SpecialPowers._getQuotaManager().storageInitialized();
+  request.callback = callback;
+
+  return request;
+}
+
+function temporaryStorageInitialized(callback) {
+  let request = SpecialPowers._getQuotaManager().temporaryStorageInitialized();
+  request.callback = callback;
+
+  return request;
+}
+
+function init(callback) {
+  let request = SpecialPowers._getQuotaManager().init();
+  request.callback = callback;
+
+  return request;
+}
+
+function initTemporaryStorage(callback) {
+  let request = SpecialPowers._getQuotaManager().initTemporaryStorage();
+  request.callback = callback;
+
+  return request;
+}
+
+function initPersistentOrigin(principal, callback) {
+  let request = SpecialPowers._getQuotaManager().initializePersistentOrigin(
+    principal
+  );
+  request.callback = callback;
+
+  return request;
+}
+
+function initTemporaryOrigin(persistence, principal, callback) {
+  let request = SpecialPowers._getQuotaManager().initializeTemporaryOrigin(
+    persistence,
+    principal
+  );
+  request.callback = callback;
+
+  return request;
+}
+
+function getFullOriginMetadata(persistence, principal, callback) {
+  const request = SpecialPowers._getQuotaManager().getFullOriginMetadata(
+    persistence,
+    principal
+  );
+  request.callback = callback;
+
+  return request;
+}
+
+function clearClient(principal, persistence, client, callback) {
+  let request = SpecialPowers._getQuotaManager().clearStoragesForPrincipal(
+    principal,
+    persistence,
+    client
+  );
+  request.callback = callback;
+
+  return request;
+}
+
+function clearOrigin(principal, persistence, callback) {
+  let request = SpecialPowers._getQuotaManager().clearStoragesForPrincipal(
+    principal,
+    persistence
+  );
+  request.callback = callback;
+
+  return request;
+}
+
+function resetClient(principal, client) {
+  let request = Services.qms.resetStoragesForPrincipal(
+    principal,
+    "default",
+    client
+  );
+
+  return request;
+}
+
+function persist(principal, callback) {
+  let request = SpecialPowers._getQuotaManager().persist(principal);
+  request.callback = callback;
+
+  return request;
+}
+
+function persisted(principal, callback) {
+  let request = SpecialPowers._getQuotaManager().persisted(principal);
+  request.callback = callback;
+
+  return request;
+}
+
+function estimateOrigin(principal, callback) {
+  let request = SpecialPowers._getQuotaManager().estimate(principal);
+  request.callback = callback;
+
+  return request;
+}
+
+function listOrigins(callback) {
+  let request = SpecialPowers._getQuotaManager().listOrigins(callback);
+  request.callback = callback;
+
+  return request;
+}
+
+function getPersistedFromMetadata(readBuffer) {
+  const persistedPosition = 8; // Persisted state is stored in the 9th byte
+  let view =
+    readBuffer instanceof Uint8Array ? readBuffer : new Uint8Array(readBuffer);
+
+  return !!view[persistedPosition];
+}
+
+function grabResultAndContinueHandler(request) {
+  testGenerator.next(request.result);
+}
+
+function grabUsageAndContinueHandler(request) {
+  testGenerator.next(request.result.usage);
+}
+
+function getUsage(usageHandler, getAll) {
+  let request = SpecialPowers._getQuotaManager().getUsage(usageHandler, getAll);
+
+  return request;
+}
+
+function getOriginUsage(principal, fromMemory = false) {
+  let request = Services.qms.getUsageForPrincipal(
+    principal,
+    function() {},
+    fromMemory
+  );
+
+  return request;
+}
+
+function getCurrentUsage(usageHandler) {
+  let principal = Cc["@mozilla.org/systemprincipal;1"].createInstance(
+    Ci.nsIPrincipal
+  );
+  let request = SpecialPowers._getQuotaManager().getUsageForPrincipal(
+    principal,
+    usageHandler
+  );
+
+  return request;
+}
+
+function getPrincipal(url, attr = {}) {
+  let uri = Cc["@mozilla.org/network/io-service;1"]
+    .getService(Ci.nsIIOService)
+    .newURI(url);
+  let ssm = Cc["@mozilla.org/scriptsecuritymanager;1"].getService(
+    Ci.nsIScriptSecurityManager
+  );
+  return ssm.createContentPrincipal(uri, attr);
+}
+
+var SpecialPowers = {
+  getBoolPref(prefName) {
+    return this._getPrefs().getBoolPref(prefName);
+  },
+
+  setBoolPref(prefName, value) {
+    this._getPrefs().setBoolPref(prefName, value);
+  },
+
+  setIntPref(prefName, value) {
+    this._getPrefs().setIntPref(prefName, value);
+  },
+
+  clearUserPref(prefName) {
+    this._getPrefs().clearUserPref(prefName);
+  },
+
+  _getPrefs() {
+    let prefService = Cc["@mozilla.org/preferences-service;1"].getService(
+      Ci.nsIPrefService
+    );
+    return prefService.getBranch(null);
+  },
+
+  _getQuotaManager() {
+    return Cc["@mozilla.org/dom/quota-manager-service;1"].getService(
+      Ci.nsIQuotaManagerService
+    );
+  },
+};
+
+function installPackages(packageRelativePaths) {
+  if (packageRelativePaths.length != 2) {
+    throw new Error("Unsupported number of package relative paths");
+  }
+
+  for (const packageRelativePath of packageRelativePaths) {
+    installPackage(packageRelativePath);
+  }
+}
+
+// Take current storage structure on disk and compare it with the expected
+// structure. The expected structure is defined in JSON and consists of a per
+// test package definition and a shared package definition. The shared package
+// definition should contain unknown stuff which needs to be properly handled
+// in all situations.
+function verifyStorage(packageDefinitionRelativePaths, key) {
+  if (packageDefinitionRelativePaths.length != 2) {
+    throw new Error("Unsupported number of package definition relative paths");
+  }
+
+  function verifyEntries(entries, name, indent = "") {
+    log(`${indent}Verifying ${name} entries`);
+
+    indent += "  ";
+
+    for (const entry of entries) {
+      const maybeName = entry.name;
+
+      log(`${indent}Verifying entry ${maybeName}`);
+
+      let hasName = false;
+      let hasDir = false;
+      let hasEntries = false;
+
+      for (const property in entry) {
+        switch (property) {
+          case "note":
+          case "todo":
+            break;
+
+          case "name":
+            hasName = true;
+            break;
+
+          case "dir":
+            hasDir = true;
+            break;
+
+          case "entries":
+            hasEntries = true;
+            break;
+
+          default:
+            throw new Error(`Unknown property ${property}`);
+        }
+      }
+
+      if (!hasName) {
+        throw new Error("An entry must have the name property");
+      }
+
+      if (!hasDir) {
+        throw new Error("An entry must have the dir property");
+      }
+
+      if (hasEntries && !entry.dir) {
+        throw new Error("An entry can't have entries if it's not a directory");
+      }
+
+      if (hasEntries) {
+        verifyEntries(entry.entries, entry.name, indent);
+      }
+    }
+  }
+
+  function getCurrentEntries() {
+    log("Getting current entries");
+
+    function getEntryForFile(file) {
+      let entry = {
+        name: file.leafName,
+        dir: file.isDirectory(),
+      };
+
+      if (file.isDirectory()) {
+        const enumerator = file.directoryEntries;
+        let nextFile;
+        while ((nextFile = enumerator.nextFile)) {
+          if (!entry.entries) {
+            entry.entries = [];
+          }
+          entry.entries.push(getEntryForFile(nextFile));
+        }
+      }
+
+      return entry;
+    }
+
+    let entries = [];
+
+    let file = getRelativeFile("indexedDB");
+    if (file.exists()) {
+      entries.push(getEntryForFile(file));
+    }
+
+    file = getRelativeFile("storage");
+    if (file.exists()) {
+      entries.push(getEntryForFile(file));
+    }
+
+    file = getRelativeFile("storage.sqlite");
+    if (file.exists()) {
+      entries.push(getEntryForFile(file));
+    }
+
+    verifyEntries(entries, "current");
+
+    return entries;
+  }
+
+  function getEntriesFromPackageDefinition(
+    packageDefinitionRelativePath,
+    lookupKey
+  ) {
+    log(`Getting ${lookupKey} entries from ${packageDefinitionRelativePath}`);
+
+    const currentDir = Services.dirsvc.get("CurWorkD", Ci.nsIFile);
+    const file = getRelativeFile(
+      packageDefinitionRelativePath + ".json",
+      currentDir
+    );
+
+    const fileInputStream = Cc[
+      "@mozilla.org/network/file-input-stream;1"
+    ].createInstance(Ci.nsIFileInputStream);
+    fileInputStream.init(file, -1, -1, 0);
+
+    const scriptableInputStream = Cc[
+      "@mozilla.org/scriptableinputstream;1"
+    ].createInstance(Ci.nsIScriptableInputStream);
+    scriptableInputStream.init(fileInputStream);
+
+    const data = scriptableInputStream.readBytes(
+      scriptableInputStream.available()
+    );
+
+    const obj = JSON.parse(data);
+
+    const result = obj.find(({ key: elementKey }) => elementKey == lookupKey);
+
+    if (!result) {
+      throw new Error("The file doesn't contain an element for given key");
+    }
+
+    if (!result.entries) {
+      throw new Error("The element doesn't have the entries property");
+    }
+
+    verifyEntries(result.entries, lookupKey);
+
+    return result.entries;
+  }
+
+  function addSharedEntries(expectedEntries, sharedEntries, name, indent = "") {
+    log(`${indent}Checking common ${name} entries`);
+
+    indent += "  ";
+
+    for (const sharedEntry of sharedEntries) {
+      const expectedEntry = expectedEntries.find(
+        ({ name: elementName }) => elementName == sharedEntry.name
+      );
+
+      if (expectedEntry) {
+        log(`${indent}Checking common entry ${sharedEntry.name}`);
+
+        if (!expectedEntry.dir || !sharedEntry.dir) {
+          throw new Error("A common entry must be a directory");
+        }
+
+        if (!expectedEntry.entries && !sharedEntry.entries) {
+          throw new Error("A common entry must not be a leaf");
+        }
+
+        if (sharedEntry.entries) {
+          if (!expectedEntry.entries) {
+            expectedEntry.entries = [];
+          }
+
+          addSharedEntries(
+            expectedEntry.entries,
+            sharedEntry.entries,
+            sharedEntry.name,
+            indent
+          );
+        }
+      } else {
+        log(`${indent}Adding entry ${sharedEntry.name}`);
+        expectedEntries.push(sharedEntry);
+      }
+    }
+  }
+
+  function compareEntries(currentEntries, expectedEntries, name, indent = "") {
+    log(`${indent}Comparing ${name} entries`);
+
+    indent += "  ";
+
+    if (currentEntries.length != expectedEntries.length) {
+      throw new Error("Entries must have the same length");
+    }
+
+    for (const currentEntry of currentEntries) {
+      log(`${indent}Comparing entry ${currentEntry.name}`);
+
+      const expectedEntry = expectedEntries.find(
+        ({ name: elementName }) => elementName == currentEntry.name
+      );
+
+      if (!expectedEntry) {
+        throw new Error("Cannot find a matching entry");
+      }
+
+      if (expectedEntry.dir != currentEntry.dir) {
+        throw new Error("The dir property doesn't match");
+      }
+
+      if (
+        (expectedEntry.entries && !currentEntry.entries) ||
+        (!expectedEntry.entries && currentEntry.entries)
+      ) {
+        throw new Error("The entries property doesn't match");
+      }
+
+      if (expectedEntry.entries) {
+        compareEntries(
+          currentEntry.entries,
+          expectedEntry.entries,
+          currentEntry.name,
+          indent
+        );
+      }
+    }
+  }
+
+  const currentEntries = getCurrentEntries();
+
+  log("Stringified current entries: " + JSON.stringify(currentEntries));
+
+  const expectedEntries = getEntriesFromPackageDefinition(
+    packageDefinitionRelativePaths[0],
+    key
+  );
+  const sharedEntries = getEntriesFromPackageDefinition(
+    packageDefinitionRelativePaths[1],
+    key
+  );
+
+  addSharedEntries(expectedEntries, sharedEntries, key);
+
+  log("Stringified expected entries: " + JSON.stringify(expectedEntries));
+
+  compareEntries(currentEntries, expectedEntries, key);
+}
+
+async function verifyInitializationStatus(
+  expectStorageIsInitialized,
+  expectTemporaryStorageIsInitialized
+) {
+  if (!expectStorageIsInitialized && expectTemporaryStorageIsInitialized) {
+    throw new Error("Invalid expectation");
+  }
+
+  let request = storageInitialized();
+  await requestFinished(request);
+
+  const storageIsInitialized = request.result;
+
+  request = temporaryStorageInitialized();
+  await requestFinished(request);
+
+  const temporaryStorageIsInitialized = request.result;
+
+  ok(
+    !(!storageIsInitialized && temporaryStorageIsInitialized),
+    "Initialization status is consistent"
+  );
+
+  if (expectStorageIsInitialized) {
+    ok(storageIsInitialized, "Storage is initialized");
+  } else {
+    ok(!storageIsInitialized, "Storage is not initialized");
+  }
+
+  if (expectTemporaryStorageIsInitialized) {
+    ok(temporaryStorageIsInitialized, "Temporary storage is initialized");
+  } else {
+    ok(!temporaryStorageIsInitialized, "Temporary storage is not initialized");
+  }
+}
diff --git a/dom/quota/test/xpcshell/common/utils.js b/dom/quota/test/xpcshell/common/utils.js
new file mode 100644
index 0000000000..ee21c90cf2
--- /dev/null
+++ b/dom/quota/test/xpcshell/common/utils.js
@@ -0,0 +1,47 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+function getOriginDir(persistence, origin) {
+  return getRelativeFile(`storage/${persistence}/${origin}`);
+}
+
+function getMetadataFile(persistence, origin) {
+  const metadataFile = getOriginDir(persistence, origin);
+  metadataFile.append(".metadata-v2");
+  return metadataFile;
+}
+
+function populateRepository(persistence) {
+  const originDir = getOriginDir(persistence, "https+++good-example.com");
+  originDir.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+}
+
+function makeRepositoryUnusable(persistence) {
+  // For the purpose of testing, we make a repository unusable by creating an
+  // origin directory with the metadata file created as a directory (not a
+  // file).
+  const metadataFile = getMetadataFile(persistence, "https+++bad-example.com");
+  metadataFile.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+}
+
+async function fillOrigin(principal, size) {
+  let database = getSimpleDatabase(principal);
+
+  let request = database.open("data");
+  await requestFinished(request);
+
+  try {
+    request = database.write(getBuffer(size));
+    await requestFinished(request);
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  request = database.close();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/createLocalStorage_profile.zip b/dom/quota/test/xpcshell/createLocalStorage_profile.zip
new file mode 100644
index 0000000000..d5958dbd59
--- /dev/null
+++ b/dom/quota/test/xpcshell/createLocalStorage_profile.zip
diff --git a/dom/quota/test/xpcshell/defaultStorageDirectory_shared.json b/dom/quota/test/xpcshell/defaultStorageDirectory_shared.json
new file mode 100644
index 0000000000..a59cebdc87
--- /dev/null
+++ b/dom/quota/test/xpcshell/defaultStorageDirectory_shared.json
@@ -0,0 +1,109 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInitTemporaryStorage",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {"name":"ls-archive.sqlite","dir":false},
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "default",
+            "dir": true,
+            "todo": "Add entry invalid+++example.com once bug 1594075 is fixed",
+            "entries": [
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "todo": "Add entry invalid+++example.com once bug 1594075 is fixed",
+            "entries": [
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/defaultStorageDirectory_shared.zip b/dom/quota/test/xpcshell/defaultStorageDirectory_shared.zip
new file mode 100644
index 0000000000..61e5b60a87
--- /dev/null
+++ b/dom/quota/test/xpcshell/defaultStorageDirectory_shared.zip
diff --git a/dom/quota/test/xpcshell/getUsage_profile.zip b/dom/quota/test/xpcshell/getUsage_profile.zip
new file mode 100644
index 0000000000..5144112bde
--- /dev/null
+++ b/dom/quota/test/xpcshell/getUsage_profile.zip
diff --git a/dom/quota/test/xpcshell/groupMismatch_profile.zip b/dom/quota/test/xpcshell/groupMismatch_profile.zip
new file mode 100644
index 0000000000..182b013de0
--- /dev/null
+++ b/dom/quota/test/xpcshell/groupMismatch_profile.zip
diff --git a/dom/quota/test/xpcshell/head.js b/dom/quota/test/xpcshell/head.js
new file mode 100644
index 0000000000..bf9ba22ce3
--- /dev/null
+++ b/dom/quota/test/xpcshell/head.js
@@ -0,0 +1,14 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../";
+
+loadScript("dom/quota/test/xpcshell/common/head.js");
+
+function loadScript(path) {
+  let uri = Services.io.newFileURI(do_get_file(depth + path));
+  Services.scriptloader.loadSubScript(uri.spec);
+}
diff --git a/dom/quota/test/xpcshell/indexedDBDirectory_shared.json b/dom/quota/test/xpcshell/indexedDBDirectory_shared.json
new file mode 100644
index 0000000000..6e3d63bafc
--- /dev/null
+++ b/dom/quota/test/xpcshell/indexedDBDirectory_shared.json
@@ -0,0 +1,35 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "indexedDB",
+        "dir": true,
+        "entries": [
+          { "name": "invalid+++example.com", "dir": true },
+          { "name": "foo.bar", "dir": false }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/indexedDBDirectory_shared.zip b/dom/quota/test/xpcshell/indexedDBDirectory_shared.zip
new file mode 100644
index 0000000000..6b959e7525
--- /dev/null
+++ b/dom/quota/test/xpcshell/indexedDBDirectory_shared.zip
diff --git a/dom/quota/test/xpcshell/make_unknownFiles.js b/dom/quota/test/xpcshell/make_unknownFiles.js
new file mode 100644
index 0000000000..dd8213ade4
--- /dev/null
+++ b/dom/quota/test/xpcshell/make_unknownFiles.js
@@ -0,0 +1,172 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+async function testSteps() {
+  const principal = getPrincipal("http://example.com");
+
+  const repoRelativePath = "storage/default";
+  const originRelativePath = `${repoRelativePath}/http+++example.com`;
+
+  let unknownFileCounter = 1;
+  let unknownDirCounter = 1;
+
+  function createUnknownFileIn(dirRelativePath, recursive) {
+    const dir = getRelativeFile(dirRelativePath);
+
+    let file = dir.clone();
+    file.append("foo" + unknownFileCounter + ".bar");
+
+    const ostream = Cc[
+      "@mozilla.org/network/file-output-stream;1"
+    ].createInstance(Ci.nsIFileOutputStream);
+
+    ostream.init(file, -1, parseInt("0644", 8), 0);
+
+    ostream.write("x".repeat(unknownFileCounter), unknownFileCounter);
+
+    ostream.close();
+
+    unknownFileCounter++;
+
+    if (recursive) {
+      const entries = dir.directoryEntries;
+      while ((file = entries.nextFile)) {
+        if (file.isDirectory()) {
+          createUnknownFileIn(dirRelativePath + "/" + file.leafName);
+        }
+      }
+    }
+  }
+
+  function createUnknownDirectoryIn(dirRelativePath) {
+    createUnknownFileIn(dirRelativePath + "/foo" + unknownDirCounter++);
+  }
+
+  // storage.sqlite and storage/ls-archive.sqlite
+  {
+    const request = init();
+    await requestFinished(request);
+  }
+
+  // Unknown file in the repository
+  {
+    createUnknownFileIn(repoRelativePath);
+  }
+
+  // Unknown file and unknown directory in the origin directory
+  {
+    let request = init();
+    await requestFinished(request);
+
+    request = initTemporaryStorage();
+    await requestFinished(request);
+
+    request = initTemporaryOrigin("default", principal);
+    await requestFinished(request);
+
+    ok(request.result === true, "The origin directory was created");
+
+    createUnknownFileIn(originRelativePath);
+    createUnknownDirectoryIn(originRelativePath);
+  }
+
+  // Unknown files in idb client directory and its subdirectories and unknown
+  // directory in .files directory
+  {
+    const request = indexedDB.openForPrincipal(principal, "myIndexedDB");
+    await openDBRequestUpgradeNeeded(request);
+
+    const database = request.result;
+
+    const objectStore = database.createObjectStore("Blobs", {});
+
+    objectStore.add(getNullBlob(200), 42);
+
+    await openDBRequestSucceeded(request);
+
+    database.close();
+
+    createUnknownFileIn(`${originRelativePath}/idb`);
+    createUnknownFileIn(
+      `${originRelativePath}/idb/2320029346mByDIdnedxe.files`
+    );
+    createUnknownDirectoryIn(
+      `${originRelativePath}/idb/2320029346mByDIdnedxe.files`
+    );
+    createUnknownFileIn(
+      `${originRelativePath}/idb/2320029346mByDIdnedxe.files/journals`
+    );
+  }
+
+  // Unknown files in cache client directory and its subdirectories
+  {
+    async function sandboxScript() {
+      const cache = await caches.open("myCache");
+      const request = new Request("http://example.com/index.html");
+      const response = new Response("hello world");
+      await cache.put(request, response);
+    }
+
+    const sandbox = new Cu.Sandbox(principal, {
+      wantGlobalProperties: ["caches", "fetch"],
+    });
+
+    const promise = new Promise(function(resolve, reject) {
+      sandbox.resolve = resolve;
+      sandbox.reject = reject;
+    });
+
+    Cu.evalInSandbox(
+      sandboxScript.toSource() + " sandboxScript().then(resolve, reject);",
+      sandbox
+    );
+    await promise;
+
+    createUnknownFileIn(`${originRelativePath}/cache`);
+    createUnknownFileIn(
+      `${originRelativePath}/cache/morgue`,
+      /* recursive */ true
+    );
+  }
+
+  // Unknown file and unknown directory in sdb client directory
+  {
+    const database = getSimpleDatabase(principal);
+
+    let request = database.open("mySimpleDB");
+    await requestFinished(request);
+
+    request = database.write(getBuffer(100));
+    await requestFinished(request);
+
+    request = database.close();
+    await requestFinished(request);
+
+    createUnknownFileIn(`${originRelativePath}/sdb`);
+    createUnknownDirectoryIn(`${originRelativePath}/sdb`);
+  }
+
+  // Unknown file and unknown directory in ls client directory
+  {
+    Services.prefs.setBoolPref("dom.storage.testing", true);
+    Services.prefs.setBoolPref("dom.storage.client_validation", false);
+
+    const storage = Services.domStorageManager.createStorage(
+      null,
+      principal,
+      principal,
+      ""
+    );
+
+    storage.setItem("foo", "bar");
+
+    storage.close();
+
+    createUnknownFileIn(`${originRelativePath}/ls`);
+    createUnknownDirectoryIn(`${originRelativePath}/ls`);
+  }
+}
diff --git a/dom/quota/test/xpcshell/make_unsetLastAccessTime.js b/dom/quota/test/xpcshell/make_unsetLastAccessTime.js
new file mode 100644
index 0000000000..9be377e4f3
--- /dev/null
+++ b/dom/quota/test/xpcshell/make_unsetLastAccessTime.js
@@ -0,0 +1,25 @@
+/*
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+*/
+
+async function testSteps() {
+  const originDirPath = "storage/default/https+++foo.example.com";
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Creating an empty origin directory");
+
+  let originDir = getRelativeFile(originDirPath);
+  originDir.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  // The metadata file should be now restored.
+}
diff --git a/dom/quota/test/xpcshell/originMismatch_profile.json b/dom/quota/test/xpcshell/originMismatch_profile.json
new file mode 100644
index 0000000000..5e1cb50631
--- /dev/null
+++ b/dom/quota/test/xpcshell/originMismatch_profile.json
@@ -0,0 +1,74 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.example.com",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata-v2", "dir": false },
+                  { "name": "cache",
+                     "dir": true,
+                     "entries": [{ "name": ".padding", "dir": false }]
+                  }
+                ]
+              },
+              { "name": "http+++www.example.com.", "dir": true  },
+              {
+                "name": "http+++www.example.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata-v2", "dir": false },
+                  { "name": "cache",
+                     "dir": true,
+                     "entries": [{ "name": ".padding", "dir": false }]
+                  }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInitTemporaryStorage",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "http+++www.example.com.",
+                "dir": true,
+                "entries": [{ "name": ".metadata-v2", "dir": false }]
+              },
+              {
+                "name": "http+++www.example.org.",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata-v2", "dir": false },
+                  { "name": "cache", "dir": true }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/originMismatch_profile.zip b/dom/quota/test/xpcshell/originMismatch_profile.zip
new file mode 100644
index 0000000000..dd5795736f
--- /dev/null
+++ b/dom/quota/test/xpcshell/originMismatch_profile.zip
diff --git a/dom/quota/test/xpcshell/persistentStorageDirectory_shared.json b/dom/quota/test/xpcshell/persistentStorageDirectory_shared.json
new file mode 100644
index 0000000000..8d36293bbf
--- /dev/null
+++ b/dom/quota/test/xpcshell/persistentStorageDirectory_shared.json
@@ -0,0 +1,57 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              { "name": "invalid+++example.com", "dir": true },
+              { "name": "foo.bar", "dir": false }
+            ]
+          }
+        ]
+      }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/persistentStorageDirectory_shared.zip b/dom/quota/test/xpcshell/persistentStorageDirectory_shared.zip
new file mode 100644
index 0000000000..b80bfe904b
--- /dev/null
+++ b/dom/quota/test/xpcshell/persistentStorageDirectory_shared.zip
diff --git a/dom/quota/test/xpcshell/removeLocalStorage1_profile.zip b/dom/quota/test/xpcshell/removeLocalStorage1_profile.zip
new file mode 100644
index 0000000000..19e971433c
--- /dev/null
+++ b/dom/quota/test/xpcshell/removeLocalStorage1_profile.zip
diff --git a/dom/quota/test/xpcshell/removeLocalStorage2_profile.zip b/dom/quota/test/xpcshell/removeLocalStorage2_profile.zip
new file mode 100644
index 0000000000..04d1a3462b
--- /dev/null
+++ b/dom/quota/test/xpcshell/removeLocalStorage2_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/head.js b/dom/quota/test/xpcshell/telemetry/head.js
new file mode 100644
index 0000000000..5c36d82ca6
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/head.js
@@ -0,0 +1,14 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../../";
+
+loadScript("dom/quota/test/xpcshell/common/head.js");
+
+function loadScript(path) {
+  let uri = Services.io.newFileURI(do_get_file(depth + path));
+  Services.scriptloader.loadSubScript(uri.spec);
+}
diff --git a/dom/quota/test/xpcshell/telemetry/test_qm_first_initialization_attempt.js b/dom/quota/test/xpcshell/telemetry/test_qm_first_initialization_attempt.js
new file mode 100644
index 0000000000..eafbc95754
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/test_qm_first_initialization_attempt.js
@@ -0,0 +1,867 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+const { TelemetryTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TelemetryTestUtils.sys.mjs"
+);
+
+const storageDirName = "storage";
+const storageFileName = "storage.sqlite";
+const indexedDBDirName = "indexedDB";
+const persistentStorageDirName = "storage/persistent";
+const histogramName = "QM_FIRST_INITIALIZATION_ATTEMPT";
+
+const testcases = [
+  {
+    mainKey: "Storage",
+    async setup(expectedInitResult) {
+      if (!expectedInitResult) {
+        // Make the database unusable by creating it as a directory (not a
+        // file).
+        const storageFile = getRelativeFile(storageFileName);
+        storageFile.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "TemporaryStorage",
+    async setup(expectedInitResult) {
+      // We need to initialize storage before populating the repositories. If
+      // we don't do that, the storage directory created for the repositories
+      // would trigger storage upgrades (from version 0 to current version).
+      let request = init();
+      await requestFinished(request);
+
+      populateRepository("temporary");
+      populateRepository("default");
+
+      if (!expectedInitResult) {
+        makeRepositoryUnusable("temporary");
+        makeRepositoryUnusable("default");
+      }
+    },
+    initFunction: initTemporaryStorage,
+    getExpectedSnapshots() {
+      const expectedSnapshotsInNightly = {
+        initFailure: {
+          Storage: {
+            values: [0, 1, 0],
+          },
+          TemporaryRepository: {
+            values: [1, 0],
+          },
+          DefaultRepository: {
+            values: [1, 0],
+          },
+          // mainKey
+          TemporaryStorage: {
+            values: [1, 0],
+          },
+        },
+        initFailureThenSuccess: {
+          Storage: {
+            values: [0, 2, 0],
+          },
+          TemporaryRepository: {
+            values: [1, 1, 0],
+          },
+          DefaultRepository: {
+            values: [1, 1, 0],
+          },
+          // mainKey
+          TemporaryStorage: {
+            values: [1, 1, 0],
+          },
+        },
+      };
+
+      const expectedSnapshotsInOthers = {
+        initFailure: {
+          Storage: {
+            values: [0, 1, 0],
+          },
+          TemporaryRepository: {
+            values: [1, 0],
+          },
+          // mainKey
+          TemporaryStorage: {
+            values: [1, 0],
+          },
+        },
+        initFailureThenSuccess: {
+          Storage: {
+            values: [0, 2, 0],
+          },
+          TemporaryRepository: {
+            values: [1, 1, 0],
+          },
+          DefaultRepository: {
+            values: [0, 1, 0],
+          },
+          // mainKey
+          TemporaryStorage: {
+            values: [1, 1, 0],
+          },
+        },
+      };
+
+      return AppConstants.NIGHTLY_BUILD
+        ? expectedSnapshotsInNightly
+        : expectedSnapshotsInOthers;
+    },
+  },
+  {
+    mainKey: "DefaultRepository",
+    async setup(expectedInitResult) {
+      // See the comment for "TemporaryStorage".
+      let request = init();
+      await requestFinished(request);
+
+      populateRepository("default");
+
+      if (!expectedInitResult) {
+        makeRepositoryUnusable("default");
+      }
+    },
+    initFunction: initTemporaryStorage,
+    expectedSnapshots: {
+      initFailure: {
+        Storage: {
+          values: [0, 1, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 1, 0],
+        },
+        // mainKey
+        DefaultRepository: {
+          values: [1, 0],
+        },
+        TemporaryStorage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        Storage: {
+          values: [0, 2, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 2, 0],
+        },
+        // mainKey
+        DefaultRepository: {
+          values: [1, 1, 0],
+        },
+        TemporaryStorage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "TemporaryRepository",
+    async setup(expectedInitResult) {
+      // See the comment for "TemporaryStorage".
+      let request = init();
+      await requestFinished(request);
+
+      populateRepository("temporary");
+
+      if (!expectedInitResult) {
+        makeRepositoryUnusable("temporary");
+      }
+    },
+    initFunction: initTemporaryStorage,
+    getExpectedSnapshots() {
+      const expectedSnapshotsInNightly = {
+        initFailure: {
+          Storage: {
+            values: [0, 1, 0],
+          },
+          // mainKey
+          TemporaryRepository: {
+            values: [1, 0],
+          },
+          DefaultRepository: {
+            values: [0, 1, 0],
+          },
+          TemporaryStorage: {
+            values: [1, 0],
+          },
+        },
+        initFailureThenSuccess: {
+          Storage: {
+            values: [0, 2, 0],
+          },
+          // mainKey
+          TemporaryRepository: {
+            values: [1, 1, 0],
+          },
+          DefaultRepository: {
+            values: [0, 2, 0],
+          },
+          TemporaryStorage: {
+            values: [1, 1, 0],
+          },
+        },
+      };
+
+      const expectedSnapshotsInOthers = {
+        initFailure: {
+          Storage: {
+            values: [0, 1, 0],
+          },
+          // mainKey
+          TemporaryRepository: {
+            values: [1, 0],
+          },
+          TemporaryStorage: {
+            values: [1, 0],
+          },
+        },
+        initFailureThenSuccess: {
+          Storage: {
+            values: [0, 2, 0],
+          },
+          // mainKey
+          TemporaryRepository: {
+            values: [1, 1, 0],
+          },
+          DefaultRepository: {
+            values: [0, 1, 0],
+          },
+          TemporaryStorage: {
+            values: [1, 1, 0],
+          },
+        },
+      };
+
+      return AppConstants.NIGHTLY_BUILD
+        ? expectedSnapshotsInNightly
+        : expectedSnapshotsInOthers;
+    },
+  },
+  {
+    mainKey: "UpgradeStorageFrom0_0To1_0",
+    async setup(expectedInitResult) {
+      // storage used prior FF 49 (storage version 0.0)
+      installPackage("version0_0_profile");
+
+      if (!expectedInitResult) {
+        installPackage("version0_0_make_it_unusable");
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeStorageFrom0_0To1_0: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeStorageFrom0_0To1_0: {
+          values: [1, 1, 0],
+        },
+        UpgradeStorageFrom1_0To2_0: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_0To2_1: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_1To2_2: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeStorageFrom1_0To2_0",
+    async setup(expectedInitResult) {
+      // storage used by FF 49-54 (storage version 1.0)
+      installPackage("version1_0_profile");
+
+      if (!expectedInitResult) {
+        installPackage("version1_0_make_it_unusable");
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeStorageFrom1_0To2_0: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeStorageFrom1_0To2_0: {
+          values: [1, 1, 0],
+        },
+        UpgradeStorageFrom2_0To2_1: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_1To2_2: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeStorageFrom2_0To2_1",
+    async setup(expectedInitResult) {
+      // storage used by FF 55-56 (storage version 2.0)
+      installPackage("version2_0_profile");
+
+      if (!expectedInitResult) {
+        installPackage("version2_0_make_it_unusable");
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeStorageFrom2_0To2_1: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeStorageFrom2_0To2_1: {
+          values: [1, 1, 0],
+        },
+        UpgradeStorageFrom2_1To2_2: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeStorageFrom2_1To2_2",
+    async setup(expectedInitResult) {
+      // storage used by FF 57-67 (storage version 2.1)
+      installPackage("version2_1_profile");
+
+      if (!expectedInitResult) {
+        installPackage("version2_1_make_it_unusable");
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeStorageFrom2_1To2_2: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeStorageFrom2_1To2_2: {
+          values: [1, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeStorageFrom2_2To2_3",
+    async setup(expectedInitResult) {
+      // storage used by FF 68-69 (storage version 2.2)
+      installPackage("version2_2_profile");
+
+      if (!expectedInitResult) {
+        installPackage(
+          "version2_2_make_it_unusable",
+          /* allowFileOverwrites */ true
+        );
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeStorageFrom2_2To2_3: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeStorageFrom2_2To2_3: {
+          values: [1, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeFromIndexedDBDirectory",
+    async setup(expectedInitResult) {
+      const indexedDBDir = getRelativeFile(indexedDBDirName);
+      indexedDBDir.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+
+      if (!expectedInitResult) {
+        // "indexedDB" directory will be moved under "storage" directory and at
+        // the same time renamed to "persistent". Create a storage file to cause
+        // the moves to fail.
+        const storageFile = getRelativeFile(storageDirName);
+        storageFile.create(Ci.nsIFile.NORMAL_FILE_TYPE, 0o666);
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeFromIndexedDBDirectory: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeFromIndexedDBDirectory: {
+          values: [1, 1, 0],
+        },
+        UpgradeFromPersistentStorageDirectory: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom0_0To1_0: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom1_0To2_0: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_0To2_1: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_1To2_2: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "UpgradeFromPersistentStorageDirectory",
+    async setup(expectedInitResult) {
+      const persistentStorageDir = getRelativeFile(persistentStorageDirName);
+      persistentStorageDir.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+
+      if (!expectedInitResult) {
+        // Create a metadata directory to break creating or upgrading directory
+        // metadata files.
+        const metadataDir = getRelativeFile(
+          "storage/persistent/https+++bad.example.com/.metadata"
+        );
+        metadataDir.create(Ci.nsIFile.DIRECTORY_TYPE, 0o755);
+      }
+    },
+    initFunction: init,
+    expectedSnapshots: {
+      initFailure: {
+        // mainKey
+        UpgradeFromPersistentStorageDirectory: {
+          values: [1, 0],
+        },
+        Storage: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        // mainKey
+        UpgradeFromPersistentStorageDirectory: {
+          values: [1, 1, 0],
+        },
+        UpgradeStorageFrom0_0To1_0: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom1_0To2_0: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_0To2_1: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_1To2_2: {
+          values: [0, 1, 0],
+        },
+        UpgradeStorageFrom2_2To2_3: {
+          values: [0, 1, 0],
+        },
+        Storage: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "PersistentOrigin",
+    async setup(expectedInitResult) {
+      // We need to initialize storage before creating the origin files. If we
+      // don't do that, the storage directory created for the origin files
+      // would trigger storage upgrades (from version 0 to current version).
+      let request = init();
+      await requestFinished(request);
+
+      if (!expectedInitResult) {
+        const originFiles = [
+          getRelativeFile("storage/permanent/https+++example.com"),
+          getRelativeFile("storage/permanent/https+++example1.com"),
+          getRelativeFile("storage/default/https+++example2.com"),
+        ];
+
+        for (const originFile of originFiles) {
+          originFile.create(Ci.nsIFile.NORMAL_FILE_TYPE, 0o666);
+        }
+      }
+
+      request = initTemporaryStorage();
+      await requestFinished(request);
+    },
+    initFunctions: [
+      {
+        name: initPersistentOrigin,
+        args: [getPrincipal("https://example.com")],
+      },
+      {
+        name: initPersistentOrigin,
+        args: [getPrincipal("https://example1.com")],
+      },
+      {
+        name: initTemporaryOrigin,
+        args: ["default", getPrincipal("https://example2.com")],
+      },
+    ],
+    expectedSnapshots: {
+      initFailure: {
+        Storage: {
+          values: [0, 1, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 1, 0],
+        },
+        DefaultRepository: {
+          values: [0, 1, 0],
+        },
+        TemporaryStorage: {
+          values: [0, 1, 0],
+        },
+        // mainKey
+        PersistentOrigin: {
+          values: [2, 0],
+        },
+        TemporaryOrigin: {
+          values: [1, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        Storage: {
+          values: [0, 2, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 2, 0],
+        },
+        DefaultRepository: {
+          values: [0, 2, 0],
+        },
+        TemporaryStorage: {
+          values: [0, 2, 0],
+        },
+        // mainKey
+        PersistentOrigin: {
+          values: [2, 2, 0],
+        },
+        TemporaryOrigin: {
+          values: [1, 1, 0],
+        },
+      },
+    },
+  },
+  {
+    mainKey: "TemporaryOrigin",
+    async setup(expectedInitResult) {
+      // See the comment for "PersistentOrigin".
+      let request = init();
+      await requestFinished(request);
+
+      if (!expectedInitResult) {
+        const originFiles = [
+          getRelativeFile("storage/temporary/https+++example.com"),
+          getRelativeFile("storage/default/https+++example.com"),
+          getRelativeFile("storage/default/https+++example1.com"),
+          getRelativeFile("storage/permanent/https+++example2.com"),
+        ];
+
+        for (const originFile of originFiles) {
+          originFile.create(Ci.nsIFile.NORMAL_FILE_TYPE, 0o666);
+        }
+      }
+
+      request = initTemporaryStorage();
+      await requestFinished(request);
+    },
+    initFunctions: [
+      {
+        name: initTemporaryOrigin,
+        args: ["temporary", getPrincipal("https://example.com")],
+      },
+      {
+        name: initTemporaryOrigin,
+        args: ["default", getPrincipal("https://example.com")],
+      },
+      {
+        name: initTemporaryOrigin,
+        args: ["default", getPrincipal("https://example1.com")],
+      },
+      {
+        name: initPersistentOrigin,
+        args: [getPrincipal("https://example2.com")],
+      },
+    ],
+    // Only the first result of EnsureTemporaryOriginIsInitialized per origin
+    // should be reported. Thus, only the results for (temporary, example.com),
+    // and (default, example1.com) should be reported.
+    expectedSnapshots: {
+      initFailure: {
+        Storage: {
+          values: [0, 1, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 1, 0],
+        },
+        DefaultRepository: {
+          values: [0, 1, 0],
+        },
+        TemporaryStorage: {
+          values: [0, 1, 0],
+        },
+        PersistentOrigin: {
+          values: [1, 0],
+        },
+        // mainKey
+        TemporaryOrigin: {
+          values: [2, 0],
+        },
+      },
+      initFailureThenSuccess: {
+        Storage: {
+          values: [0, 2, 0],
+        },
+        TemporaryRepository: {
+          values: [0, 2, 0],
+        },
+        DefaultRepository: {
+          values: [0, 2, 0],
+        },
+        TemporaryStorage: {
+          values: [0, 2, 0],
+        },
+        PersistentOrigin: {
+          values: [1, 1, 0],
+        },
+        // mainKey
+        TemporaryOrigin: {
+          values: [2, 2, 0],
+        },
+      },
+    },
+  },
+];
+
+loadScript("dom/quota/test/xpcshell/common/utils.js");
+
+function verifyHistogram(histogram, mainKey, expectedSnapshot) {
+  const snapshot = histogram.snapshot();
+
+  ok(
+    mainKey in snapshot,
+    `The histogram ${histogram.name()} must contain the main key ${mainKey}`
+  );
+
+  const keys = Object.keys(snapshot);
+
+  is(
+    keys.length,
+    Object.keys(expectedSnapshot).length,
+    `The number of keys must match the expected number of keys for ` +
+      `${histogram.name()}`
+  );
+
+  for (const key of keys) {
+    ok(
+      key in expectedSnapshot,
+      `The key ${key} must match the expected keys for ${histogram.name()}`
+    );
+
+    const values = Object.entries(snapshot[key].values);
+    const expectedValues = expectedSnapshot[key].values;
+
+    is(
+      values.length,
+      expectedValues.length,
+      `The number of values should match the expected number of values for ` +
+        `${histogram.name()}`
+    );
+
+    for (let [i, val] of values) {
+      is(
+        val,
+        expectedValues[i],
+        `Expected counts should match for ${histogram.name()} at index ${i}`
+      );
+    }
+  }
+}
+
+async function testSteps() {
+  let request;
+  for (const testcase of testcases) {
+    const mainKey = testcase.mainKey;
+
+    info(`Verifying ${histogramName} histogram for the main key ${mainKey}`);
+
+    const histogram = TelemetryTestUtils.getAndClearKeyedHistogram(
+      histogramName
+    );
+
+    for (const expectedInitResult of [false, true]) {
+      info(
+        `Verifying the histogram when the initialization ` +
+          `${expectedInitResult ? "failed and then succeeds" : "fails"}`
+      );
+
+      await testcase.setup(expectedInitResult);
+
+      const msg = `Should ${expectedInitResult ? "not " : ""} have thrown`;
+
+      // Call the initialization function twice, so we can verify below that
+      // only the first initialization attempt has been reported.
+      for (let i = 0; i < 2; ++i) {
+        let initFunctions;
+
+        if (testcase.initFunctions) {
+          initFunctions = testcase.initFunctions;
+        } else {
+          initFunctions = [
+            {
+              name: testcase.initFunction,
+              args: [],
+            },
+          ];
+        }
+
+        for (const initFunction of initFunctions) {
+          request = initFunction.name(...initFunction.args);
+          try {
+            await requestFinished(request);
+            ok(expectedInitResult, msg);
+          } catch (ex) {
+            ok(!expectedInitResult, msg);
+          }
+        }
+      }
+
+      const expectedSnapshots = testcase.getExpectedSnapshots
+        ? testcase.getExpectedSnapshots()
+        : testcase.expectedSnapshots;
+
+      const expectedSnapshot = expectedInitResult
+        ? expectedSnapshots.initFailureThenSuccess
+        : expectedSnapshots.initFailure;
+
+      verifyHistogram(histogram, mainKey, expectedSnapshot);
+
+      // The first initialization attempt has been reported in the histogram
+      // and any new attemps wouldn't be reported if we didn't reset or clear
+      // the storage here. We need a clean profile for the next iteration
+      // anyway.
+      // However, the clear storage operation needs initialized storage, so
+      // clearing can fail if the storage is unusable and it can also increase
+      // some of the telemetry counters. Instead of calling clear, we can just
+      // call reset and clear profile manually.
+      request = reset();
+      await requestFinished(request);
+
+      const indexedDBDir = getRelativeFile(indexedDBDirName);
+      if (indexedDBDir.exists()) {
+        indexedDBDir.remove(false);
+      }
+
+      const storageDir = getRelativeFile(storageDirName);
+      if (storageDir.exists()) {
+        storageDir.remove(true);
+      }
+
+      const storageFile = getRelativeFile(storageFileName);
+      if (storageFile.exists()) {
+        // It could be a non empty directory, so remove it recursively.
+        storageFile.remove(true);
+      }
+    }
+  }
+}
diff --git a/dom/quota/test/xpcshell/telemetry/version0_0_make_it_unusable.zip b/dom/quota/test/xpcshell/telemetry/version0_0_make_it_unusable.zip
new file mode 100644
index 0000000000..92dcfb777e
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version0_0_make_it_unusable.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version0_0_profile.zip b/dom/quota/test/xpcshell/telemetry/version0_0_profile.zip
new file mode 100644
index 0000000000..2fb0f525c2
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version0_0_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version1_0_make_it_unusable.zip b/dom/quota/test/xpcshell/telemetry/version1_0_make_it_unusable.zip
new file mode 100644
index 0000000000..92dcfb777e
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version1_0_make_it_unusable.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version1_0_profile.zip b/dom/quota/test/xpcshell/telemetry/version1_0_profile.zip
new file mode 100644
index 0000000000..6169f439c1
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version1_0_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_0_make_it_unusable.zip b/dom/quota/test/xpcshell/telemetry/version2_0_make_it_unusable.zip
new file mode 100644
index 0000000000..92dcfb777e
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_0_make_it_unusable.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_0_profile.zip b/dom/quota/test/xpcshell/telemetry/version2_0_profile.zip
new file mode 100644
index 0000000000..465f53cea9
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_0_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_1_make_it_unusable.zip b/dom/quota/test/xpcshell/telemetry/version2_1_make_it_unusable.zip
new file mode 100644
index 0000000000..92dcfb777e
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_1_make_it_unusable.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_1_profile.zip b/dom/quota/test/xpcshell/telemetry/version2_1_profile.zip
new file mode 100644
index 0000000000..81463235ab
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_1_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_2_make_it_unusable.zip b/dom/quota/test/xpcshell/telemetry/version2_2_make_it_unusable.zip
new file mode 100644
index 0000000000..b6b8eecabf
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_2_make_it_unusable.zip
diff --git a/dom/quota/test/xpcshell/telemetry/version2_2_profile.zip b/dom/quota/test/xpcshell/telemetry/version2_2_profile.zip
new file mode 100644
index 0000000000..e572726cca
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/version2_2_profile.zip
diff --git a/dom/quota/test/xpcshell/telemetry/xpcshell.ini b/dom/quota/test/xpcshell/telemetry/xpcshell.ini
new file mode 100644
index 0000000000..bb5655f103
--- /dev/null
+++ b/dom/quota/test/xpcshell/telemetry/xpcshell.ini
@@ -0,0 +1,20 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+[DEFAULT]
+head = head.js
+support-files =
+  version0_0_make_it_unusable.zip
+  version0_0_profile.zip
+  version1_0_make_it_unusable.zip
+  version1_0_profile.zip
+  version2_0_make_it_unusable.zip
+  version2_0_profile.zip
+  version2_1_make_it_unusable.zip
+  version2_1_profile.zip
+  version2_2_make_it_unusable.zip
+  version2_2_profile.zip
+
+[test_qm_first_initialization_attempt.js]
+skip-if = appname == "thunderbird"
diff --git a/dom/quota/test/xpcshell/tempMetadataCleanup_profile.zip b/dom/quota/test/xpcshell/tempMetadataCleanup_profile.zip
new file mode 100644
index 0000000000..da1de0979b
--- /dev/null
+++ b/dom/quota/test/xpcshell/tempMetadataCleanup_profile.zip
diff --git a/dom/quota/test/xpcshell/test_allowListFiles.js b/dom/quota/test/xpcshell/test_allowListFiles.js
new file mode 100644
index 0000000000..04c64c2ef5
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_allowListFiles.js
@@ -0,0 +1,61 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify thoes unexpected files are in the allow list of
+ * QuotaManager. They aren't expected in the repository but if there are,
+ * QuotaManager shouldn't fail to initialize an origin and getting usage, though
+ * those files aren't managed by QuotaManager.
+ */
+
+async function testSteps() {
+  const allowListFiles = [
+    ".dot-file",
+    "desktop.ini",
+    "Desktop.ini",
+    "Thumbs.db",
+    "thumbs.db",
+  ];
+
+  for (let allowListFile of allowListFiles) {
+    info("Testing " + allowListFile + " in the repository");
+
+    info("Initializing");
+
+    let request = init();
+    await requestFinished(request);
+
+    info("Creating unknown files");
+
+    for (let dir of ["persistenceType dir", "origin dir"]) {
+      let dirPath =
+        dir == "persistenceType dir"
+          ? "storage/default/"
+          : "storage/default/http+++example.com/";
+      let file = getRelativeFile(dirPath + allowListFile);
+      file.create(Ci.nsIFile.NORMAL_FILE_TYPE, parseInt("0644", 8));
+    }
+
+    info("Initializing temporary storage");
+
+    request = initTemporaryStorage();
+    await requestFinished(request);
+
+    info("Resetting");
+
+    request = reset();
+    await requestFinished(request);
+
+    info("Getting usage");
+
+    request = getCurrentUsage(continueToNextStepSync);
+    await requestFinished(request);
+
+    info("Clearing");
+
+    request = clear();
+    await requestFinished(request);
+  }
+}
diff --git a/dom/quota/test/xpcshell/test_bad_origin_directory.js b/dom/quota/test/xpcshell/test_bad_origin_directory.js
new file mode 100644
index 0000000000..3058e31473
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_bad_origin_directory.js
@@ -0,0 +1,36 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const invalidOrigin = {
+    url: "ftp://ftp.invalid.origin",
+    path: "storage/default/ftp+++ftp.invalid.origin",
+  };
+
+  info("Persisting an invalid origin");
+
+  let invalidPrincipal = getPrincipal(invalidOrigin.url);
+
+  let request = persist(invalidPrincipal, continueToNextStepSync);
+  yield undefined;
+
+  ok(
+    request.resultCode === NS_ERROR_FAILURE,
+    "Persist() failed because of the invalid origin"
+  );
+  ok(request.result === null, "The request result is null");
+
+  let originDir = getRelativeFile(invalidOrigin.path);
+  let exists = originDir.exists();
+  ok(!exists, "Directory for invalid origin doesn't exist");
+
+  request = persisted(invalidPrincipal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persisted() succeeded");
+  ok(!request.result, "The origin isn't persisted since the operation failed");
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_basics.js b/dom/quota/test/xpcshell/test_basics.js
new file mode 100644
index 0000000000..b72c2feb9f
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_basics.js
@@ -0,0 +1,143 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const storageFile = "storage.sqlite";
+
+  const metadataFiles = [
+    {
+      path: "storage/permanent/chrome/.metadata",
+      shouldExistAfterInit: false,
+    },
+
+    {
+      path: "storage/permanent/chrome/.metadata-tmp",
+      shouldExistAfterInit: false,
+    },
+
+    {
+      path: "storage/permanent/chrome/.metadata-v2",
+      shouldExistAfterInit: true,
+    },
+
+    {
+      path: "storage/permanent/chrome/.metadata-v2-tmp",
+      shouldExistAfterInit: false,
+    },
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(false, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Getting usage");
+
+  getCurrentUsage(grabUsageAndContinueHandler);
+  let usage = yield undefined;
+
+  ok(usage == 0, "Usage is zero");
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(true, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(false, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Installing package");
+
+  // The profile contains just one empty IndexedDB database. The file
+  // create_db.js in the package was run locally, specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  // mach xpcshell-test --interactive dom/quota/test/xpcshell/create_db.js
+  installPackage("basics_profile");
+
+  info("Getting usage");
+
+  getCurrentUsage(grabUsageAndContinueHandler);
+  usage = yield undefined;
+
+  ok(usage > 0, "Usage is not zero");
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(true, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Checking storage file");
+
+  let file = getRelativeFile(storageFile);
+
+  let exists = file.exists();
+  ok(!exists, "Storage file doesn't exist");
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(false, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Initializing");
+
+  request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  exists = file.exists();
+  ok(exists, "Storage file does exist");
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(true, false).then(continueToNextStepSync);
+  yield undefined;
+
+  info("Initializing origin");
+
+  request = initPersistentOrigin(getCurrentPrincipal(), continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  ok(request.result, "Origin directory was created");
+
+  for (let metadataFile of metadataFiles) {
+    file = getRelativeFile(metadataFile.path);
+
+    exists = file.exists();
+
+    if (metadataFile.shouldExistAfterInit) {
+      ok(exists, "Metadata file does exist");
+    } else {
+      ok(!exists, "Metadata file doesn't exist");
+    }
+  }
+
+  info("Verifying initialization status");
+
+  verifyInitializationStatus(true, false).then(continueToNextStepSync);
+
+  yield undefined;
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_clearStoragesForOriginAttributesPattern.js b/dom/quota/test/xpcshell/test_clearStoragesForOriginAttributesPattern.js
new file mode 100644
index 0000000000..096cf2be70
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_clearStoragesForOriginAttributesPattern.js
@@ -0,0 +1,58 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const baseRelativePath = "storage/default";
+  const userContextForRemoval = 2;
+
+  const origins = [
+    {
+      userContextId: 1,
+      baseDirName: "https+++example.com",
+    },
+
+    {
+      userContextId: userContextForRemoval,
+      baseDirName: "https+++example.com",
+    },
+
+    // TODO: Uncomment this once bug 1638831 is fixed.
+    /*
+    {
+      userContextId: userContextForRemoval,
+      baseDirName: "https+++example.org",
+    },
+    */
+  ];
+
+  function getOriginDirectory(origin) {
+    return getRelativeFile(
+      `${baseRelativePath}/${origin.baseDirName}^userContextId=` +
+        `${origin.userContextId}`
+    );
+  }
+
+  let request = init();
+  await requestFinished(request);
+
+  for (const origin of origins) {
+    const directory = getOriginDirectory(origin);
+    directory.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+  }
+
+  request = Services.qms.clearStoragesForOriginAttributesPattern(
+    `{ "userContextId": ${userContextForRemoval} }`
+  );
+  await requestFinished(request);
+
+  for (const origin of origins) {
+    const directory = getOriginDirectory(origin);
+    if (origin.userContextId === userContextForRemoval) {
+      ok(!directory.exists(), "Origin directory should have been removed");
+    } else {
+      ok(directory.exists(), "Origin directory shouldn't have been removed");
+    }
+  }
+}
diff --git a/dom/quota/test/xpcshell/test_clearStoragesForPrincipal.js b/dom/quota/test/xpcshell/test_clearStoragesForPrincipal.js
new file mode 100644
index 0000000000..1e8bed54b7
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_clearStoragesForPrincipal.js
@@ -0,0 +1,56 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is an xpcshell test for clearStoragesForPrincipal. It verifies that
+ * if the removing client is the last client in the targeting origin, then it
+ * is expected to remove the origin directory as well.
+ */
+
+async function testSteps() {
+  const testingOrigins = [
+    {
+      origin: "http://example.com",
+      path: "storage/default/http+++example.com/",
+      only_idb: false,
+    },
+    {
+      origin: "http://www.mozilla.org",
+      path: "storage/default/http+++www.mozilla.org/",
+      only_idb: true,
+    },
+  ];
+  const removingClient = "idb";
+
+  info("Installing package to create the environment");
+  // The package is manually created and it contains:
+  // - storage/default/http+++www.mozilla.org/idb/
+  // - storage/default/http+++www.example.com/idb/
+  // - storage/default/http+++www.example.com/cache/
+  installPackage("clearStoragesForPrincipal_profile");
+
+  let request;
+  let file;
+  for (let i = 0; i < testingOrigins.length; ++i) {
+    info("Clearing");
+    request = clearClient(
+      getPrincipal(testingOrigins[i].origin),
+      null,
+      removingClient
+    );
+    await requestFinished(request);
+
+    info("Verifying");
+    file = getRelativeFile(testingOrigins[i].path + removingClient);
+    ok(!file.exists(), "Client file doesn't exist");
+
+    file = getRelativeFile(testingOrigins[i].path);
+    if (testingOrigins[i].only_idb) {
+      todo(!file.exists(), "Origin file doesn't exist");
+    } else {
+      ok(file.exists(), "Origin file does exist");
+    }
+  }
+}
diff --git a/dom/quota/test/xpcshell/test_createLocalStorage.js b/dom/quota/test/xpcshell/test_createLocalStorage.js
new file mode 100644
index 0000000000..a99a458713
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_createLocalStorage.js
@@ -0,0 +1,155 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const webAppsStoreFile = "webappsstore.sqlite";
+  const lsArchiveFile = "storage/ls-archive.sqlite";
+  const lsArchiveTmpFile = "storage/ls-archive-tmp.sqlite";
+
+  function checkArchiveFileNotExists() {
+    info("Checking archive tmp file");
+
+    let archiveTmpFile = getRelativeFile(lsArchiveTmpFile);
+
+    let exists = archiveTmpFile.exists();
+    ok(!exists, "archive tmp file doesn't exist");
+
+    info("Checking archive file");
+
+    let archiveFile = getRelativeFile(lsArchiveFile);
+
+    exists = archiveFile.exists();
+    ok(!exists, "archive file doesn't exist");
+  }
+
+  function checkArchiveFileExists() {
+    info("Checking archive tmp file");
+
+    let archiveTmpFile = getRelativeFile(lsArchiveTmpFile);
+
+    let exists = archiveTmpFile.exists();
+    ok(!exists, "archive tmp file doesn't exist");
+
+    info("Checking archive file");
+
+    let archiveFile = getRelativeFile(lsArchiveFile);
+
+    exists = archiveFile.exists();
+    ok(exists, "archive file does exist");
+
+    info("Checking archive file size");
+
+    let fileSize = archiveFile.fileSize;
+    ok(fileSize > 0, "archive file size is greater than zero");
+  }
+
+  // Profile 1 - Nonexistent apps store file.
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  let appsStoreFile = getRelativeFile(webAppsStoreFile);
+
+  let exists = appsStoreFile.exists();
+  ok(!exists, "apps store file doesn't exist");
+
+  checkArchiveFileNotExists();
+
+  try {
+    request = init();
+    await requestFinished(request);
+
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  checkArchiveFileExists();
+
+  // Profile 2 - apps store file is a directory.
+  info("Clearing");
+
+  request = clear();
+  await requestFinished(request);
+
+  appsStoreFile.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+
+  checkArchiveFileNotExists();
+
+  try {
+    request = init();
+    await requestFinished(request);
+
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  checkArchiveFileExists();
+
+  appsStoreFile.remove(true);
+
+  // Profile 3 - Corrupted apps store file.
+  info("Clearing");
+
+  request = clear();
+  await requestFinished(request);
+
+  let ostream = Cc["@mozilla.org/network/file-output-stream;1"].createInstance(
+    Ci.nsIFileOutputStream
+  );
+  ostream.init(appsStoreFile, -1, parseInt("0644", 8), 0);
+  ostream.write("foobar", 6);
+  ostream.close();
+
+  checkArchiveFileNotExists();
+
+  try {
+    request = init();
+    await requestFinished(request);
+
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  checkArchiveFileExists();
+
+  appsStoreFile.remove(false);
+
+  // Profile 4 - Nonupdateable apps store file.
+  info("Clearing");
+
+  request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains storage.sqlite and webappsstore.sqlite
+  // webappstore.sqlite was taken from FF 54 to force an upgrade.
+  // There's just one record in the webappsstore2 table. The record was
+  // modified by renaming the origin attribute userContextId to userContextKey.
+  // This triggers an error during the upgrade.
+  installPackage("createLocalStorage_profile");
+
+  let fileSize = appsStoreFile.fileSize;
+  ok(fileSize > 0, "apps store file size is greater than zero");
+
+  checkArchiveFileNotExists();
+
+  try {
+    request = init();
+    await requestFinished(request);
+
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  checkArchiveFileExists();
+
+  appsStoreFile.remove(false);
+}
diff --git a/dom/quota/test/xpcshell/test_estimateOrigin.js b/dom/quota/test/xpcshell/test_estimateOrigin.js
new file mode 100644
index 0000000000..31d6f01686
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_estimateOrigin.js
@@ -0,0 +1,80 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/xpcshell/common/utils.js");
+
+async function verifyOriginEstimation(principal, expectedUsage, expectedLimit) {
+  info("Estimating origin");
+
+  const request = estimateOrigin(principal);
+  await requestFinished(request);
+
+  is(request.result.usage, expectedUsage, "Correct usage");
+  is(request.result.limit, expectedLimit, "Correct limit");
+}
+
+async function testSteps() {
+  // The group limit is calculated as 20% of the global limit and the minimum
+  // value of the group limit is 10 MB.
+
+  const groupLimitKB = 10 * 1024;
+  const groupLimitBytes = groupLimitKB * 1024;
+  const globalLimitKB = groupLimitKB * 5;
+  const globalLimitBytes = globalLimitKB * 1024;
+
+  info("Setting limits");
+
+  setGlobalLimit(globalLimitKB);
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Filling origins");
+
+  await fillOrigin(getPrincipal("https://foo1.example1.com"), 100);
+  await fillOrigin(getPrincipal("https://foo2.example1.com"), 200);
+  await fillOrigin(getPrincipal("https://foo1.example2.com"), 300);
+  await fillOrigin(getPrincipal("https://foo2.example2.com"), 400);
+
+  info("Verifying origin estimations");
+
+  await verifyOriginEstimation(
+    getPrincipal("https://foo1.example1.com"),
+    300,
+    groupLimitBytes
+  );
+  await verifyOriginEstimation(
+    getPrincipal("https://foo2.example1.com"),
+    300,
+    groupLimitBytes
+  );
+  await verifyOriginEstimation(
+    getPrincipal("https://foo1.example2.com"),
+    700,
+    groupLimitBytes
+  );
+  await verifyOriginEstimation(
+    getPrincipal("https://foo2.example2.com"),
+    700,
+    groupLimitBytes
+  );
+
+  info("Persisting origin");
+
+  request = persist(getPrincipal("https://foo2.example2.com"));
+  await requestFinished(request);
+
+  info("Verifying origin estimation");
+
+  await verifyOriginEstimation(
+    getPrincipal("https://foo2.example2.com"),
+    1000,
+    globalLimitBytes
+  );
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_getUsage.js b/dom/quota/test/xpcshell/test_getUsage.js
new file mode 100644
index 0000000000..282894beeb
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_getUsage.js
@@ -0,0 +1,129 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const origins = [
+    {
+      origin: "http://example.com",
+      persisted: false,
+      usage: 49152,
+    },
+
+    {
+      origin: "http://localhost",
+      persisted: false,
+      usage: 147456,
+    },
+
+    {
+      origin: "http://www.mozilla.org",
+      persisted: true,
+      usage: 98304,
+    },
+  ];
+
+  const allOrigins = [
+    {
+      origin: "chrome",
+      persisted: false,
+      usage: 147456,
+    },
+
+    {
+      origin: "http://example.com",
+      persisted: false,
+      usage: 49152,
+    },
+
+    {
+      origin: "http://localhost",
+      persisted: false,
+      usage: 147456,
+    },
+
+    {
+      origin: "http://www.mozilla.org",
+      persisted: true,
+      usage: 98304,
+    },
+  ];
+
+  function verifyResult(result, expectedOrigins) {
+    ok(result instanceof Array, "Got an array object");
+    ok(result.length == expectedOrigins.length, "Correct number of elements");
+
+    info("Sorting elements");
+
+    result.sort(function(a, b) {
+      let originA = a.origin;
+      let originB = b.origin;
+
+      if (originA < originB) {
+        return -1;
+      }
+      if (originA > originB) {
+        return 1;
+      }
+      return 0;
+    });
+
+    info("Verifying elements");
+
+    for (let i = 0; i < result.length; i++) {
+      let a = result[i];
+      let b = expectedOrigins[i];
+      ok(a.origin == b.origin, "Origin equals");
+      ok(a.persisted == b.persisted, "Persisted equals");
+      ok(a.usage == b.usage, "Usage equals");
+    }
+  }
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Getting usage");
+
+  getUsage(grabResultAndContinueHandler, /* getAll */ true);
+  let result = yield undefined;
+
+  info("Verifying result");
+
+  verifyResult(result, []);
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Installing package");
+
+  // The profile contains IndexedDB databases placed across the repositories.
+  // The file create_db.js in the package was run locally, specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  // mach xpcshell-test --interactive dom/quota/test/xpcshell/create_db.js
+  installPackage("getUsage_profile");
+
+  info("Getting usage");
+
+  getUsage(grabResultAndContinueHandler, /* getAll */ false);
+  result = yield undefined;
+
+  info("Verifying result");
+
+  verifyResult(result, origins);
+
+  info("Getting usage");
+
+  getUsage(grabResultAndContinueHandler, /* getAll */ true);
+  result = yield undefined;
+
+  info("Verifying result");
+
+  verifyResult(result, allOrigins);
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_groupMismatch.js b/dom/quota/test/xpcshell/test_groupMismatch.js
new file mode 100644
index 0000000000..41a72d51ad
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_groupMismatch.js
@@ -0,0 +1,74 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that metadata files with old group information
+ * get updated. See bug 1535995.
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+async function testSteps() {
+  const metadataFile = getRelativeFile(
+    "storage/default/https+++foo.bar.mozilla-iot.org/.metadata-v2"
+  );
+
+  async function readMetadataFile() {
+    let file = await File.createFromNsIFile(metadataFile);
+
+    let buffer = await new Promise(resolve => {
+      let reader = new FileReader();
+      reader.onloadend = () => resolve(reader.result);
+      reader.readAsArrayBuffer(file);
+    });
+
+    return buffer;
+  }
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains one initialized origin directory, a script for origin
+  // initialization and the storage database:
+  // - storage/default/https+++foo.bar.mozilla-iot.org
+  // - create_db.js
+  // - storage.sqlite
+  // The file create_db.js in the package was run locally, specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  //   mach xpcshell-test --interactive dom/localstorage/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Manually change the group in .metadata and .metadata-v2 from
+  //    "bar.mozilla-iot.org" to "mozilla-iot.org".
+  // 2. Remove the folder "storage/temporary".
+  // 3. Remove the file "storage/ls-archive.sqlite".
+  installPackage("groupMismatch_profile");
+
+  info("Reading out contents of metadata file");
+
+  let metadataBuffer = await readMetadataFile();
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Reading out contents of metadata file");
+
+  let metadataBuffer2 = await readMetadataFile();
+
+  info("Verifying blobs differ");
+
+  ok(!compareBuffers(metadataBuffer, metadataBuffer2), "Metadata differ");
+}
diff --git a/dom/quota/test/xpcshell/test_initTemporaryStorage.js b/dom/quota/test/xpcshell/test_initTemporaryStorage.js
new file mode 100644
index 0000000000..d6a6cfcb5f
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_initTemporaryStorage.js
@@ -0,0 +1,49 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify initTemporaryStorage() does call
+ * QuotaManager::EnsureTemporaryStorageIsInitialized() which does various
+ * things, for example, it restores the directory metadata if it's broken or
+ * missing.
+ */
+
+async function testSteps() {
+  const originDirPath = "storage/default/https+++foo.example.com";
+  const metadataFileName = ".metadata-v2";
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Verifying initialization status");
+
+  await verifyInitializationStatus(true, false);
+
+  info("Creating an empty directory");
+
+  let originDir = getRelativeFile(originDirPath);
+  originDir.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+
+  info("Initializing the temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info(
+    "Verifying directory metadata was restored after calling " +
+      "initTemporaryStorage()"
+  );
+
+  let metadataFile = originDir.clone();
+  metadataFile.append(metadataFileName);
+
+  ok(metadataFile.exists(), "Directory metadata file does exist");
+
+  info("Verifying initialization status");
+
+  await verifyInitializationStatus(true, true);
+}
diff --git a/dom/quota/test/xpcshell/test_listOrigins.js b/dom/quota/test/xpcshell/test_listOrigins.js
new file mode 100644
index 0000000000..223e6a9401
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_listOrigins.js
@@ -0,0 +1,80 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const origins = [
+    "https://example.com",
+    "https://localhost",
+    "https://www.mozilla.org",
+  ];
+
+  function verifyResult(result, expectedOrigins) {
+    ok(result instanceof Array, "Got an array object");
+    ok(result.length == expectedOrigins.length, "Correct number of elements");
+
+    info("Sorting elements");
+
+    result.sort(function(a, b) {
+      if (a < b) {
+        return -1;
+      }
+      if (a > b) {
+        return 1;
+      }
+      return 0;
+    });
+
+    info("Verifying elements");
+
+    for (let i = 0; i < result.length; i++) {
+      ok(result[i] == expectedOrigins[i], "Result matches expected origin");
+    }
+  }
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Listing origins");
+
+  request = listOrigins();
+  await requestFinished(request);
+
+  info("Verifying result");
+
+  verifyResult(request.result, []);
+
+  info("Clearing");
+
+  request = clear();
+  await requestFinished(request);
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    request = initTemporaryOrigin("default", getPrincipal(origin));
+    await requestFinished(request);
+  }
+
+  info("Listing origins");
+
+  request = listOrigins();
+  await requestFinished(request);
+
+  info("Verifying result");
+
+  verifyResult(request.result, origins);
+}
diff --git a/dom/quota/test/xpcshell/test_originEndsWithDot.js b/dom/quota/test/xpcshell/test_originEndsWithDot.js
new file mode 100644
index 0000000000..8301b3292d
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_originEndsWithDot.js
@@ -0,0 +1,70 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+async function testSteps() {
+  // First, ensure the origin can be initialized and used by a client that uses
+  // SQLite databases.
+
+  // Todo: consider using simpleDB once it supports using storage for SQLite.
+  info("Testing SQLite database with an origin that ends with a dot");
+
+  const principal = getPrincipal("https://example.com.");
+  let request = indexedDB.openForPrincipal(principal, "myIndexedDB");
+  await openDBRequestUpgradeNeeded(request);
+
+  info("Testing simple operations");
+
+  const database = request.result;
+
+  const objectStore = database.createObjectStore("Blobs", {});
+
+  objectStore.add(getNullBlob(200), 42);
+
+  await openDBRequestSucceeded(request);
+
+  database.close();
+
+  info("Reseting");
+
+  request = reset();
+  await requestFinished(request);
+
+  let idbDB = getRelativeFile(
+    "storage/default/https+++example.com./idb/2320029346mByDIdnedxe.sqlite"
+  );
+  ok(idbDB.exists(), "IDB database was created successfully");
+
+  // Second, ensure storage initialization works fine with the origin.
+
+  info("Testing storage initialization and temporary storage initialization");
+
+  request = init();
+  await requestFinished(request);
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  // Third, ensure QMS APIs that touch the client directory for the origin work
+  // fine.
+
+  info("Testing getUsageForPrincipal");
+
+  request = getOriginUsage(principal);
+  await requestFinished(request);
+
+  ok(
+    request.result instanceof Ci.nsIQuotaOriginUsageResult,
+    "The result is nsIQuotaOriginUsageResult instance"
+  );
+  ok(request.result.usage > 0, "Total usage is not empty");
+  ok(request.result.fileUsage > 0, "File usage is not empty");
+
+  info("Testing clearStoragesForPrincipal");
+
+  request = clearOrigin(principal, "default");
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_originMismatch.js b/dom/quota/test/xpcshell/test_originMismatch.js
new file mode 100644
index 0000000000..23186977b2
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_originMismatch.js
@@ -0,0 +1,75 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that temporary storage initialization should
+ * succeed while there is an origin directory that has an inconsistency between
+ * its directory name and the origin name in its directory metadata file.
+ */
+
+async function testSteps() {
+  const packages = ["originMismatch_profile", "defaultStorageDirectory_shared"];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing package");
+
+  // The profile contains:
+  // - storage.sqlite (v2_3)
+  // (A) Verify we are okay while the directory that we want to restore has
+  // already existed.
+  // - storage/default/http+++www.example.com/.metadata-v2
+  //   (origin: http://www.example.com.)
+  // - storage/default/http+++www.example.com/cache/.padding
+  // - storage/default/http+++www.example.com./
+  // (B) Verify restoring origin directory succeed.
+  // - storage/default/http+++www.example.org/.metadata-v2
+  //   (origin: http://www.example.org.)
+  // - storage/default/http+++www.example.org/cache/.padding
+  //
+  // ToDo: Test case like:
+  // - storage/default/http+++www.example.org(1)/.metadata-v2
+  //   (origin: http://www.example.org)
+  // - storage/default/http+++www.example.org/
+  //
+  // - storage/default/http+++www.foo.com/.metadata-v2
+  //   (origin: http://www.bar.com)
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Initializing storage");
+
+  request = init();
+  await requestFinished(request);
+
+  // ToDo: Remove this code once we support unknown directories in respository
+  // (bug 1594075).
+  let invalidDir = getRelativeFile("storage/default/invalid+++example.com");
+  invalidDir.remove(true);
+  invalidDir = getRelativeFile("storage/temporary/invalid+++example.com");
+  invalidDir.remove(true);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInitTemporaryStorage");
+
+  request = clear();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_originWithCaret.js b/dom/quota/test/xpcshell/test_originWithCaret.js
new file mode 100644
index 0000000000..7afce4f5cc
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_originWithCaret.js
@@ -0,0 +1,17 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+"use strict";
+
+async function testSteps() {
+  Assert.throws(
+    () => {
+      const principal = getPrincipal("http://example.com^123");
+      getSimpleDatabase(principal);
+    },
+    /NS_ERROR_MALFORMED_URI/,
+    "^ is not allowed in the hostname"
+  );
+}
diff --git a/dom/quota/test/xpcshell/test_orpahnedQuotaObject.js b/dom/quota/test/xpcshell/test_orpahnedQuotaObject.js
new file mode 100644
index 0000000000..6cbca13d8c
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_orpahnedQuotaObject.js
@@ -0,0 +1,44 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const principal = getPrincipal("https://example.com");
+
+  info("Setting pref");
+
+  Services.prefs.setBoolPref("dom.storage.client_validation", false);
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Creating simpledb");
+
+  let database = getSimpleDatabase(principal);
+
+  request = database.open("data");
+  await requestFinished(request);
+
+  info("Creating localStorage");
+
+  let storage = Services.domStorageManager.createStorage(
+    null,
+    principal,
+    principal,
+    ""
+  );
+  storage.setItem("key", "value");
+
+  info("Clearing simpledb");
+
+  request = clearClient(principal, "default", "sdb");
+  await requestFinished(request);
+
+  info("Resetting localStorage");
+
+  request = resetClient(principal, "ls");
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_persist.js b/dom/quota/test/xpcshell/test_persist.js
new file mode 100644
index 0000000000..0920522973
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_persist.js
@@ -0,0 +1,121 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const origin = {
+    url: "http://default.test.persist",
+    path: "storage/default/http+++default.test.persist",
+    persistence: "default",
+  };
+
+  const metadataFileName = ".metadata-v2";
+
+  let principal = getPrincipal(origin.url);
+
+  info("Persisting an uninitialized origin");
+
+  // Origin directory doesn't exist yet, so only check the result for
+  // persisted().
+  let request = persisted(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persisted() succeeded");
+  ok(!request.result, "The origin is not persisted");
+
+  info("Verifying persist() does update the metadata");
+
+  request = persist(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persist() succeeded");
+
+  let originDir = getRelativeFile(origin.path);
+  let exists = originDir.exists();
+  ok(exists, "Origin directory does exist");
+
+  info("Reading out contents of metadata file");
+
+  let metadataFile = originDir.clone();
+  metadataFile.append(metadataFileName);
+
+  File.createFromNsIFile(metadataFile).then(grabArgAndContinueHandler);
+  let file = yield undefined;
+
+  let fileReader = new FileReader();
+  fileReader.onload = continueToNextStepSync;
+  fileReader.readAsArrayBuffer(file);
+  yield undefined;
+
+  let originPersisted = getPersistedFromMetadata(fileReader.result);
+  ok(originPersisted, "The origin is persisted");
+
+  info("Verifying persisted()");
+
+  request = persisted(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persisted() succeeded");
+  ok(request.result === originPersisted, "Persisted() concurs with metadata");
+
+  info("Clearing the origin");
+
+  // Clear the origin since we'll test the same directory again under different
+  // circumstances.
+  clearOrigin(principal, origin.persistence, continueToNextStepSync);
+  yield undefined;
+
+  info("Persisting an already initialized origin");
+
+  initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  initTemporaryOrigin(origin.persistence, principal, continueToNextStepSync);
+  yield undefined;
+
+  info("Reading out contents of metadata file");
+
+  fileReader = new FileReader();
+  fileReader.onload = continueToNextStepSync;
+  fileReader.readAsArrayBuffer(file);
+  yield undefined;
+
+  originPersisted = getPersistedFromMetadata(fileReader.result);
+  ok(!originPersisted, "The origin isn't persisted after clearing");
+
+  info("Verifying persisted()");
+
+  request = persisted(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persisted() succeeded");
+  ok(request.result === originPersisted, "Persisted() concurs with metadata");
+
+  info("Verifying persist() does update the metadata");
+
+  request = persist(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persist() succeeded");
+
+  info("Reading out contents of metadata file");
+
+  fileReader = new FileReader();
+  fileReader.onload = continueToNextStepSync;
+  fileReader.readAsArrayBuffer(file);
+  yield undefined;
+
+  originPersisted = getPersistedFromMetadata(fileReader.result);
+  ok(originPersisted, "The origin is persisted");
+
+  info("Verifying persisted()");
+
+  request = persisted(principal, continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode === NS_OK, "Persisted() succeeded");
+  ok(request.result === originPersisted, "Persisted() concurs with metadata");
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_persist_eviction.js b/dom/quota/test/xpcshell/test_persist_eviction.js
new file mode 100644
index 0000000000..9a62f91b50
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_persist_eviction.js
@@ -0,0 +1,82 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that normally the oldest origin will be
+ * evicted if the global limit is reached, but if the oldest origin is
+ * persisted or is an extension origin, then it won't be evicted.
+ */
+
+loadScript("dom/quota/test/xpcshell/common/utils.js");
+
+async function testSteps() {
+  // The group limit is calculated as 20% of the global limit and the minimum
+  // value of the group limit is 10 MB.
+
+  const groupLimitKB = 10 * 1024;
+  const globalLimitKB = groupLimitKB * 5;
+
+  setGlobalLimit(globalLimitKB);
+
+  let request = clear();
+  await requestFinished(request);
+
+  for (let persistOldestOrigin of [false, true]) {
+    info(
+      "Testing " +
+        (persistOldestOrigin ? "with" : "without") +
+        " persisting the oldest origin"
+    );
+
+    info(
+      "Step 0: Filling a moz-extension origin as the oldest origin with non-persisted data"
+    );
+
+    // Just a fake moz-extension origin to mock an extension origin.
+    let extUUID = "20445ca5-75f9-420e-a1d4-9cccccb5e891";
+    let spec = `moz-extension://${extUUID}`;
+    await fillOrigin(getPrincipal(spec), groupLimitKB * 1024);
+
+    info(
+      "Step 1: Filling five separate web origins to reach the global limit " +
+        "and trigger eviction"
+    );
+
+    for (let index = 1; index <= 5; index++) {
+      let spec = "http://example" + index + ".com";
+      if (index == 1 && persistOldestOrigin) {
+        request = persist(getPrincipal(spec));
+        await requestFinished(request);
+      }
+      await fillOrigin(getPrincipal(spec), groupLimitKB * 1024);
+    }
+
+    info("Step 2: Verifying origin directories");
+
+    for (let index = 1; index <= 5; index++) {
+      let path = "storage/default/http+++example" + index + ".com";
+      let file = getRelativeFile(path);
+      if (index == (persistOldestOrigin ? 2 : 1)) {
+        ok(!file.exists(), "The origin directory " + path + " doesn't exist");
+      } else {
+        ok(file.exists(), "The origin directory " + path + " does exist");
+      }
+    }
+
+    // Verify that the extension storage data has not been evicted (even if it wasn't marked as
+    // persisted and it was the less recently used origin).
+    let path = `storage/default/moz-extension+++${extUUID}`;
+    let file = getRelativeFile(path);
+    ok(file.exists(), "The origin directory " + path + "does exist");
+
+    request = clear();
+    await requestFinished(request);
+  }
+
+  resetGlobalLimit();
+
+  request = reset();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_persist_globalLimit.js b/dom/quota/test/xpcshell/test_persist_globalLimit.js
new file mode 100644
index 0000000000..8b15c26eae
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_persist_globalLimit.js
@@ -0,0 +1,82 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that persisted origins are always bounded by
+ * the global limit.
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+async function testSteps() {
+  const globalLimitKB = 1;
+
+  const principal = getPrincipal("https://persisted.example.com");
+
+  info("Setting limits");
+
+  setGlobalLimit(globalLimitKB);
+
+  let request = clear();
+  await requestFinished(request);
+
+  for (let initializeStorageBeforePersist of [false, true]) {
+    if (initializeStorageBeforePersist) {
+      info("Initializing");
+
+      request = init();
+      await requestFinished(request);
+
+      info("Initializing the temporary storage");
+
+      request = initTemporaryStorage();
+      await requestFinished(request);
+    }
+
+    info("Persisting an origin");
+
+    request = persist(principal);
+    await requestFinished(request);
+
+    info("Verifying the persisted origin is bounded by global limit");
+
+    let database = getSimpleDatabase(principal);
+
+    info("Opening a database for the persisted origin");
+
+    request = database.open("data");
+    await requestFinished(request);
+
+    try {
+      info("Writing over the limit shouldn't succeed");
+
+      request = database.write(getBuffer(globalLimitKB * 1024 + 1));
+      await requestFinished(request);
+
+      ok(false, "Should have thrown");
+    } catch (e) {
+      ok(true, "Should have thrown");
+      ok(
+        e.resultCode === NS_ERROR_FILE_NO_DEVICE_SPACE,
+        "Threw right result code"
+      );
+    }
+
+    info("Closing the database and clearing");
+
+    request = database.close();
+    await requestFinished(request);
+
+    request = clear();
+    await requestFinished(request);
+  }
+
+  info("Resetting limits");
+
+  resetGlobalLimit();
+
+  request = reset();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_persist_groupLimit.js b/dom/quota/test/xpcshell/test_persist_groupLimit.js
new file mode 100644
index 0000000000..202726299f
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_persist_groupLimit.js
@@ -0,0 +1,104 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that persisted origins are not constrained by
+ * the group limit.  It consits of these steps:
+ * - Set the limits as small as our limits allow.  This does result in needing
+ *   to perform 10 megs of writes which is a lot for a test but not horrible.
+ * - Create databases for 2 origins under the same group.
+ * - Have the foo2 origin use up the shared group quota.
+ * - Verify neither origin can write additional data (via a single byte write).
+ * - Do navigator.storage.persist() for that foo2 origin.
+ * - Verify that both origins can now write an additional byte.  This
+ *   demonstrates that:
+ *   - foo2 no longer counts against the group limit at all since foo1 can
+ *     write a byte.
+ *   - foo2 is no longer constrained by the group limit itself.
+ */
+async function testSteps() {
+  // The group limit is calculated as 20% of the global limit and the minimum
+  // value of the group limit is 10 MB.
+
+  const groupLimitKB = 10 * 1024;
+  const globalLimitKB = groupLimitKB * 5;
+
+  const urls = ["http://foo1.example.com", "http://foo2.example.com"];
+
+  const foo2Index = 1;
+
+  let index;
+
+  info("Setting limits");
+
+  setGlobalLimit(globalLimitKB);
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Opening databases");
+
+  let databases = [];
+  for (index = 0; index < urls.length; index++) {
+    let database = getSimpleDatabase(getPrincipal(urls[index]));
+
+    request = database.open("data");
+    await requestFinished(request);
+
+    databases.push(database);
+  }
+
+  info("Filling up the whole group");
+
+  try {
+    request = databases[foo2Index].write(new ArrayBuffer(groupLimitKB * 1024));
+    await requestFinished(request);
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  info("Verifying no more data can be written");
+
+  for (index = 0; index < urls.length; index++) {
+    try {
+      request = databases[index].write(new ArrayBuffer(1));
+      await requestFinished(request);
+      ok(false, "Should have thrown");
+    } catch (e) {
+      ok(true, "Should have thrown");
+      ok(
+        e.resultCode == NS_ERROR_FILE_NO_DEVICE_SPACE,
+        "Threw right result code"
+      );
+    }
+  }
+
+  info("Persisting origin");
+
+  request = persist(getPrincipal(urls[foo2Index]));
+  await requestFinished(request);
+
+  info("Verifying more data data can be written");
+
+  for (index = 0; index < urls.length; index++) {
+    try {
+      request = databases[index].write(new ArrayBuffer(1));
+      await requestFinished(request);
+      ok(true, "Should not have thrown");
+    } catch (ex) {
+      ok(false, "Should not have thrown");
+    }
+  }
+
+  info("Closing databases");
+
+  for (index = 0; index < urls.length; index++) {
+    request = databases[index].close();
+    await requestFinished(request);
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_removeLocalStorage.js b/dom/quota/test/xpcshell/test_removeLocalStorage.js
new file mode 100644
index 0000000000..bae4ad1649
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_removeLocalStorage.js
@@ -0,0 +1,89 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const lsArchiveFile = "storage/ls-archive.sqlite";
+  const lsArchiveTmpFile = "storage/ls-archive-tmp.sqlite";
+  const lsDir = "storage/default/http+++localhost/ls";
+
+  info("Setting pref");
+
+  SpecialPowers.setBoolPref(
+    "dom.storage.enable_unsupported_legacy_implementation",
+    true
+  );
+
+  // Profile 1
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Installing package");
+
+  installPackage("removeLocalStorage1_profile");
+
+  info("Checking ls archive tmp file");
+
+  let archiveTmpFile = getRelativeFile(lsArchiveTmpFile);
+
+  let exists = archiveTmpFile.exists();
+  ok(exists, "ls archive tmp file does exist");
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Checking ls archive file");
+
+  exists = archiveTmpFile.exists();
+  ok(!exists, "ls archive tmp file doesn't exist");
+
+  // Profile 2
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Installing package");
+
+  installPackage("removeLocalStorage2_profile");
+
+  info("Checking ls archive file");
+
+  let archiveFile = getRelativeFile(lsArchiveFile);
+
+  exists = archiveFile.exists();
+  ok(exists, "ls archive file does exist");
+
+  info("Checking ls dir");
+
+  let dir = getRelativeFile(lsDir);
+
+  exists = dir.exists();
+  ok(exists, "ls directory does exist");
+
+  info("Initializing");
+
+  request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Checking ls archive file");
+
+  exists = archiveFile.exists();
+  ok(!exists, "ls archive file doesn't exist");
+
+  info("Checking ls dir");
+
+  exists = dir.exists();
+  ok(!exists, "ls directory doesn't exist");
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_simpledb.js b/dom/quota/test/xpcshell/test_simpledb.js
new file mode 100644
index 0000000000..b698d778e0
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_simpledb.js
@@ -0,0 +1,6 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+loadScript("dom/quota/test/common/test_simpledb.js");
diff --git a/dom/quota/test/xpcshell/test_specialOrigins.js b/dom/quota/test/xpcshell/test_specialOrigins.js
new file mode 100644
index 0000000000..d66700d359
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_specialOrigins.js
@@ -0,0 +1,55 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const origins = [
+    {
+      path: "storage/default/file+++UNIVERSAL_FILE_URI_ORIGIN",
+      url: "file:///Test/test.html",
+      persistence: "default",
+    },
+  ];
+
+  info("Setting pref");
+
+  SpecialPowers.setBoolPref("security.fileuri.strict_origin_policy", false);
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Creating origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.path);
+    originDir.create(Ci.nsIFile.DIRECTORY_TYPE, parseInt("0755", 8));
+  }
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Initializing origin directories");
+
+  for (let origin of origins) {
+    let result;
+
+    try {
+      request = initTemporaryOrigin(
+        origin.persistence,
+        getPrincipal(origin.url)
+      );
+      result = await requestFinished(request);
+
+      ok(true, "Should not have thrown");
+    } catch (ex) {
+      ok(false, "Should not have thrown");
+    }
+
+    ok(!result, "Origin directory wasn't created");
+  }
+}
diff --git a/dom/quota/test/xpcshell/test_storagePressure.js b/dom/quota/test/xpcshell/test_storagePressure.js
new file mode 100644
index 0000000000..2e95b2d749
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_storagePressure.js
@@ -0,0 +1,135 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that the storage pressure event is fired when
+ * the eviction process is not able to free some space when a quota client
+ * attempts to write over the global limit or when the global limit is reduced
+ * below the global usage.
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+function awaitStoragePressure() {
+  let promise_resolve;
+
+  let promise = new Promise(function(resolve) {
+    promise_resolve = resolve;
+  });
+
+  function observer(subject, topic) {
+    ok(true, "Got the storage pressure event");
+
+    Services.obs.removeObserver(observer, topic);
+
+    let usage = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
+    promise_resolve(usage);
+  }
+
+  Services.obs.addObserver(observer, "QuotaManager::StoragePressure");
+
+  return promise;
+}
+
+async function testSteps() {
+  const globalLimitKB = 2;
+
+  const principal = getPrincipal("https://example.com");
+
+  info("Setting limits");
+
+  setGlobalLimit(globalLimitKB);
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Persisting and filling an origin");
+
+  // We need to persist the origin first to omit the group limit checks.
+  // Otherwise, we would have to fill five separate origins.
+  request = persist(principal);
+  await requestFinished(request);
+
+  let database = getSimpleDatabase(principal);
+
+  request = database.open("data");
+  await requestFinished(request);
+
+  try {
+    request = database.write(getBuffer(globalLimitKB * 1024));
+    await requestFinished(request);
+
+    ok(true, "Should not have thrown");
+  } catch (ex) {
+    ok(false, "Should not have thrown");
+  }
+
+  info("Testing storage pressure by writing over the global limit");
+
+  info("Storing one more byte to get the storage pressure event while writing");
+
+  let promiseStoragePressure = awaitStoragePressure();
+
+  try {
+    request = database.write(getBuffer(1));
+    await requestFinished(request);
+
+    ok(false, "Should have thrown");
+  } catch (e) {
+    ok(true, "Should have thrown");
+    ok(
+      e.resultCode === NS_ERROR_FILE_NO_DEVICE_SPACE,
+      "Threw right result code"
+    );
+  }
+
+  info("Checking the storage pressure event");
+
+  let usage = await promiseStoragePressure;
+  ok(usage == globalLimitKB * 1024, "Got correct usage");
+
+  info("Testing storage pressure by reducing the global limit");
+
+  info(
+    "Reducing the global limit to get the storage pressuse event while the" +
+      " temporary storage is being initialized"
+  );
+
+  setGlobalLimit(globalLimitKB - 1);
+
+  request = reset();
+  await requestFinished(request);
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  promiseStoragePressure = awaitStoragePressure();
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Checking the storage pressure event");
+
+  usage = await promiseStoragePressure;
+  ok(usage == globalLimitKB * 1024, "Got correct usage");
+
+  info("Resetting limits");
+
+  resetGlobalLimit();
+
+  request = reset();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_tempMetadataCleanup.js b/dom/quota/test/xpcshell/test_tempMetadataCleanup.js
new file mode 100644
index 0000000000..981e1a14d3
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_tempMetadataCleanup.js
@@ -0,0 +1,45 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const tempMetadataFiles = [
+    "storage/permanent/chrome/.metadata-tmp",
+    "storage/permanent/chrome/.metadata-v2-tmp",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Installing package");
+
+  installPackage("tempMetadataCleanup_profile");
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  info("Initializing origin");
+
+  request = initPersistentOrigin(getCurrentPrincipal(), continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  ok(!request.result, "Origin directory wasn't created");
+
+  for (let tempMetadataFile of tempMetadataFiles) {
+    info("Checking temp metadata file");
+
+    let file = getRelativeFile(tempMetadataFile);
+
+    let exists = file.exists();
+    ok(!exists, "Temp metadata file doesn't exist");
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/test_unaccessedOrigins.js b/dom/quota/test/xpcshell/test_unaccessedOrigins.js
new file mode 100644
index 0000000000..93b38501f4
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_unaccessedOrigins.js
@@ -0,0 +1,168 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+const SEC_PER_MONTH = 60 * 60 * 24 * 30;
+
+async function testSteps() {
+  function getHostname(index) {
+    return "www.example" + index + ".com";
+  }
+
+  function getOrigin(index) {
+    return "https://" + getHostname(index);
+  }
+
+  function getOriginDir(index) {
+    return getRelativeFile("storage/default/https+++" + getHostname(index));
+  }
+
+  function updateOriginLastAccessTime(index, deltaSec) {
+    let originDir = getOriginDir(index);
+
+    let metadataFile = originDir.clone();
+    metadataFile.append(".metadata-v2");
+
+    let fileRandomAccessStream = Cc[
+      "@mozilla.org/network/file-random-access-stream;1"
+    ].createInstance(Ci.nsIFileRandomAccessStream);
+    fileRandomAccessStream.init(metadataFile, -1, -1, 0);
+
+    let binaryInputStream = Cc[
+      "@mozilla.org/binaryinputstream;1"
+    ].createInstance(Ci.nsIBinaryInputStream);
+    binaryInputStream.setInputStream(fileRandomAccessStream);
+
+    let lastAccessTime = binaryInputStream.read64();
+
+    let seekableStream = fileRandomAccessStream.QueryInterface(
+      Ci.nsISeekableStream
+    );
+    seekableStream.seek(Ci.nsISeekableStream.NS_SEEK_SET, 0);
+
+    binaryOutputStream = Cc["@mozilla.org/binaryoutputstream;1"].createInstance(
+      Ci.nsIBinaryOutputStream
+    );
+    binaryOutputStream.setOutputStream(fileRandomAccessStream);
+
+    binaryOutputStream.write64(lastAccessTime + deltaSec * PR_USEC_PER_SEC);
+
+    binaryOutputStream.close();
+
+    binaryInputStream.close();
+  }
+
+  function verifyOriginDir(index, shouldExist) {
+    let originDir = getOriginDir(index);
+    let exists = originDir.exists();
+    if (shouldExist) {
+      ok(exists, "Origin directory does exist");
+    } else {
+      ok(!exists, "Origin directory doesn't exist");
+    }
+  }
+
+  info("Setting prefs");
+
+  Services.prefs.setBoolPref("dom.quotaManager.loadQuotaFromCache", false);
+  Services.prefs.setBoolPref("dom.quotaManager.checkQuotaInfoLoadTime", true);
+  Services.prefs.setIntPref(
+    "dom.quotaManager.longQuotaInfoLoadTimeThresholdMs",
+    0
+  );
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Initializing origins");
+
+  for (let index = 0; index < 30; index++) {
+    request = initTemporaryOrigin("default", getPrincipal(getOrigin(index)));
+    await requestFinished(request);
+  }
+
+  info("Updating last access time of selected origins");
+
+  for (let index = 0; index < 10; index++) {
+    updateOriginLastAccessTime(index, -14 * SEC_PER_MONTH);
+  }
+
+  for (let index = 10; index < 20; index++) {
+    updateOriginLastAccessTime(index, -7 * SEC_PER_MONTH);
+  }
+
+  info("Resetting");
+
+  request = reset();
+  await requestFinished(request);
+
+  info("Setting pref");
+
+  Services.prefs.setIntPref(
+    "dom.quotaManager.unaccessedForLongTimeThresholdSec",
+    13 * SEC_PER_MONTH
+  );
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Verifying origin directories");
+
+  for (let index = 0; index < 10; index++) {
+    verifyOriginDir(index, false);
+  }
+  for (let index = 10; index < 30; index++) {
+    verifyOriginDir(index, true);
+  }
+
+  info("Resetting");
+
+  request = reset();
+  await requestFinished(request);
+
+  info("Setting pref");
+
+  Services.prefs.setIntPref(
+    "dom.quotaManager.unaccessedForLongTimeThresholdSec",
+    6 * SEC_PER_MONTH
+  );
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Verifying origin directories");
+
+  for (let index = 0; index < 20; index++) {
+    verifyOriginDir(index, false);
+  }
+  for (let index = 20; index < 30; index++) {
+    verifyOriginDir(index, true);
+  }
+
+  info("Resetting");
+
+  request = reset();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/test_unknownFiles.js b/dom/quota/test/xpcshell/test_unknownFiles.js
new file mode 100644
index 0000000000..9ddfbed56b
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_unknownFiles.js
@@ -0,0 +1,106 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that init, initTemporaryStorage,
+ * getUsageForPrincipal and clearStoragesForPrincipal are able to ignore
+ * unknown files and directories in the storage/default directory and its
+ * subdirectories.
+ */
+async function testSteps() {
+  const principal = getPrincipal("http://example.com");
+
+  async function testFunctionality(testFunction) {
+    const modes = [
+      {
+        initializedStorage: false,
+        initializedTemporaryStorage: false,
+      },
+      {
+        initializedStorage: true,
+        initializedTemporaryStorage: false,
+      },
+      {
+        initializedStorage: true,
+        initializedTemporaryStorage: true,
+      },
+    ];
+
+    for (const mode of modes) {
+      info("Clearing");
+
+      let request = clear();
+      await requestFinished(request);
+
+      info("Installing package");
+
+      // The profile contains unknown files and unknown directories placed
+      // across the repositories, origin directories and client directories.
+      // The file make_unknownFiles.js was run locally, specifically it was
+      // temporarily enabled in xpcshell.ini and then executed:
+      // mach test --interactive dom/quota/test/xpcshell/make_unknownFiles.js
+      installPackage("unknownFiles_profile");
+
+      if (mode.initializedStorage) {
+        info("Initializing storage");
+
+        request = init();
+        await requestFinished(request);
+      }
+
+      if (mode.initializedTemporaryStorage) {
+        info("Initializing temporary storage");
+
+        request = initTemporaryStorage();
+        await requestFinished(request);
+      }
+
+      info("Verifying initialization status");
+
+      await verifyInitializationStatus(
+        mode.initializedStorage,
+        mode.initializedTemporaryStorage
+      );
+
+      await testFunction(
+        mode.initializedStorage,
+        mode.initializedTemporaryStorage
+      );
+
+      info("Clearing");
+
+      request = clear();
+      await requestFinished(request);
+    }
+  }
+
+  // init and initTemporaryStorage functionality is tested in the
+  // testFunctionality function as part of the multi mode testing
+
+  info("Testing getUsageForPrincipal functionality");
+
+  await testFunctionality(async function() {
+    info("Getting origin usage");
+
+    request = getOriginUsage(principal);
+    await requestFinished(request);
+
+    ok(
+      request.result instanceof Ci.nsIQuotaOriginUsageResult,
+      "The result is nsIQuotaOriginUsageResult instance"
+    );
+    is(request.result.usage, 115025, "Correct total usage");
+    is(request.result.fileUsage, 200, "Correct file usage");
+  });
+
+  info("Testing clearStoragesForPrincipal functionality");
+
+  await testFunctionality(async function() {
+    info("Clearing origin");
+
+    request = clearOrigin(principal, "default");
+    await requestFinished(request);
+  });
+}
diff --git a/dom/quota/test/xpcshell/test_unsetLastAccessTime.js b/dom/quota/test/xpcshell/test_unsetLastAccessTime.js
new file mode 100644
index 0000000000..96155af397
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_unsetLastAccessTime.js
@@ -0,0 +1,68 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+async function testSteps() {
+  const metadataFile = getRelativeFile(
+    "storage/default/https+++foo.example.com/.metadata-v2"
+  );
+
+  function getLastAccessTime() {
+    let fileInputStream = Cc[
+      "@mozilla.org/network/file-input-stream;1"
+    ].createInstance(Ci.nsIFileInputStream);
+
+    fileInputStream.init(metadataFile, -1, -1, 0);
+
+    let binaryInputStream = Cc[
+      "@mozilla.org/binaryinputstream;1"
+    ].createInstance(Ci.nsIBinaryInputStream);
+
+    binaryInputStream.setInputStream(fileInputStream);
+
+    let lastAccessTime = BigInt.asIntN(64, BigInt(binaryInputStream.read64()));
+
+    binaryInputStream.close();
+
+    return lastAccessTime;
+  }
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains one initialized origin directory and the storage
+  // database:
+  // - storage/default/https+++foo.example.com
+  // - storage.sqlite
+  // The file make_unsetLastAccessTime.js was run locally, specifically it was
+  // temporarily enabled in xpcshell.ini and then executed:
+  // mach test --interactive dom/quota/test/xpcshell/make_unsetLastAccessTime.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/temporary".
+  // 2. Remove the file "storage/ls-archive.sqlite".
+  installPackage("unsetLastAccessTime_profile");
+
+  info("Verifying last access time");
+
+  ok(getLastAccessTime() == INT64_MIN, "Correct last access time");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Verifying last access time");
+
+  ok(getLastAccessTime() != INT64_MIN, "Correct last access time");
+}
diff --git a/dom/quota/test/xpcshell/test_validOrigins.js b/dom/quota/test/xpcshell/test_validOrigins.js
new file mode 100644
index 0000000000..4c758d6bf5
--- /dev/null
+++ b/dom/quota/test/xpcshell/test_validOrigins.js
@@ -0,0 +1,99 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// Use initOrigin to test the operation of the origin parser on a list of URLs
+// we should support. If the origin doesn't parse, then initOrigin will throw an
+// exception (and potentially MOZ_ASSERT under debug builds). Handling of
+// obsolete or invalid origins is handled in other test files.
+async function testSteps() {
+  const basePath = "storage/default/";
+  const longExampleOriginSubstring = "a".repeat(
+    255 - "https://example..com".length
+  );
+  const origins = [
+    // General
+    {
+      dirName: "https+++example.com",
+      url: "https://example.com",
+    },
+    {
+      dirName: "https+++smaug----.github.io",
+      url: "https://smaug----.github.io/",
+    },
+    // About
+    {
+      dirName: "about+home",
+      url: "about:home",
+    },
+    {
+      dirName: "about+reader",
+      url: "about:reader",
+    },
+    // IPv6
+    {
+      dirName: "https+++[++]",
+      url: "https://[::]",
+    },
+    {
+      dirName: "https+++[ffff+ffff+ffff+ffff+ffff+ffff+ffff+ffff]",
+      url: "https://[ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff]",
+    },
+    {
+      dirName: "http+++[2010+836b+4179++836b+4179]",
+      url: "http://[2010:836B:4179::836B:4179]:80",
+    },
+    {
+      dirName: "https+++[++ffff+8190+3426]",
+      url: "https://[::FFFF:129.144.52.38]",
+    },
+    // MAX_PATH on Windows (260); storage/default/https+++example.{a....a}.com
+    // should have already exceeded the MAX_PATH limitation on Windows.
+    // There is a limitation (255) for each component on Windows so that we can
+    // only let the component be 255 chars and expect the wwhole path to be
+    // greater then 260.
+    {
+      dirName: `https+++example.${longExampleOriginSubstring}.com`,
+      url: `https://example.${longExampleOriginSubstring}.com`,
+    },
+    // EndingWithPeriod
+    {
+      dirName: "https+++example.com.",
+      url: "https://example.com.",
+    },
+  ];
+
+  info("Initializing");
+
+  let request = init();
+  await requestFinished(request);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  for (let origin of origins) {
+    info(`Testing ${origin.url}`);
+
+    try {
+      request = initTemporaryOrigin("default", getPrincipal(origin.url));
+      await requestFinished(request);
+
+      ok(true, "Should not have thrown");
+    } catch (ex) {
+      ok(false, "Should not have thrown");
+    }
+
+    let dir = getRelativeFile(basePath + origin.dirName);
+    ok(dir.exists(), "Origin was created");
+    ok(
+      origin.dirName === dir.leafName,
+      `Origin ${origin.dirName} was created expectedly`
+    );
+  }
+
+  request = clear();
+  await requestFinished(request);
+}
diff --git a/dom/quota/test/xpcshell/unknownFiles_profile.zip b/dom/quota/test/xpcshell/unknownFiles_profile.zip
new file mode 100644
index 0000000000..96d636780d
--- /dev/null
+++ b/dom/quota/test/xpcshell/unknownFiles_profile.zip
diff --git a/dom/quota/test/xpcshell/unsetLastAccessTime_profile.zip b/dom/quota/test/xpcshell/unsetLastAccessTime_profile.zip
new file mode 100644
index 0000000000..2b14ca7276
--- /dev/null
+++ b/dom/quota/test/xpcshell/unsetLastAccessTime_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.json b/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.json
new file mode 100644
index 0000000000..eff5918e98
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.json
@@ -0,0 +1,64 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "https+++www.mozilla.org^userContextId=1",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "sdb",
+                    "dir": true,
+                    "entries": [{ "name": "data.sdb", "dir": false }]
+                  },
+                  { "name": ".metadata-v2", "dir":false }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "https+++www.mozilla.org^userContextId=1",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "sdb",
+                    "dir": true,
+                    "entries": [{ "name": "data.sdb", "dir": false }]
+                  },
+                  { "name": ".metadata-v2", "dir":false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.zip b/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.zip
new file mode 100644
index 0000000000..c09b503c18
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/cacheVersion1_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/head.js b/dom/quota/test/xpcshell/upgrades/head.js
new file mode 100644
index 0000000000..5c36d82ca6
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/head.js
@@ -0,0 +1,14 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// The path to the top level directory.
+const depth = "../../../../../";
+
+loadScript("dom/quota/test/xpcshell/common/head.js");
+
+function loadScript(path) {
+  let uri = Services.io.newFileURI(do_get_file(depth + path));
+  Services.scriptloader.loadSubScript(uri.spec);
+}
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.json b/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.json
new file mode 100644
index 0000000000..db66d824eb
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.json
@@ -0,0 +1,63 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "indexedDB",
+        "dir": true,
+        "entries": [
+          {
+            "name": "http+++www.mozilla.org",
+            "dir": true,
+            "entries": [{ "name": ".metadata", "dir": false }]
+          }
+        ]
+      },
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.zip b/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.zip
new file mode 100644
index 0000000000..63936ecf9a
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBAndPersistentStorageDirectory_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.json b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.json
new file mode 100644
index 0000000000..7916c25b73
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.json
@@ -0,0 +1,55 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "indexedDB",
+        "dir": true,
+        "entries": [
+          { "name": "1007+f+app+++system.gaiamobile.org", "dir": true },
+          { "name": "http+++www.mozilla.org", "dir": true },
+          { "name": "1007+t+https+++developer.cdn.mozilla.net", "dir": true }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.zip b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.zip
new file mode 100644
index 0000000000..a0a56a77df
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_flatOriginDirectories_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.json b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.json
new file mode 100644
index 0000000000..715c954915
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.json
@@ -0,0 +1,65 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "indexedDB",
+        "dir": true,
+        "entries": [
+          {
+            "name": "1007+f+app+++system.gaiamobile.org",
+            "dir": true,
+            "entries": [{ "name": ".metadata", "dir": false }]
+          },
+          {
+            "name": "http+++www.mozilla.org",
+            "dir": true,
+            "entries": [{ "name": ".metadata", "dir": false }]
+          },
+          {
+            "name": "1007+t+https+++developer.cdn.mozilla.net",
+            "dir": true,
+            "entries": [{ "name": ".metadata", "dir": false }]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.zip b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.zip
new file mode 100644
index 0000000000..589e65ec82
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/indexedDBDirectory_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/localStorageArchive1upgrade_profile.zip b/dom/quota/test/xpcshell/upgrades/localStorageArchive1upgrade_profile.zip
new file mode 100644
index 0000000000..a17b90dedf
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/localStorageArchive1upgrade_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/localStorageArchive4upgrade_profile.zip b/dom/quota/test/xpcshell/upgrades/localStorageArchive4upgrade_profile.zip
new file mode 100644
index 0000000000..cf5b29adae
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/localStorageArchive4upgrade_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/localStorageArchiveDowngrade_profile.zip b/dom/quota/test/xpcshell/upgrades/localStorageArchiveDowngrade_profile.zip
new file mode 100644
index 0000000000..2f11abe858
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/localStorageArchiveDowngrade_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.json b/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.json
new file mode 100644
index 0000000000..a25f257573
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.json
@@ -0,0 +1,63 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              }
+            ]
+          },
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.zip b/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.zip
new file mode 100644
index 0000000000..9ddd9af6a9
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentAndDefaultStorageDirectory_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.json b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.json
new file mode 100644
index 0000000000..c80a3cc283
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.json
@@ -0,0 +1,64 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              { "name": "1007+f+app+++system.gaiamobile.org", "dir": true },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.net",
+                "dir": true
+              },
+              { "name": "http+++www.mozilla.org", "dir": true }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.zip b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.zip
new file mode 100644
index 0000000000..436ebf9070
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_flatOriginDirectories_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.json b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.json
new file mode 100644
index 0000000000..98d23af161
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.json
@@ -0,0 +1,92 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "1007+f+app+++system.gaiamobile.org",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false }
+                ]
+              },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false }
+                ]
+              },
+              { "name": "http+++www.mozilla.org+8080", "dir": true }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org+8080",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.zip b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.zip
new file mode 100644
index 0000000000..0c5200adf4
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_originDirectories_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.json b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.json
new file mode 100644
index 0000000000..f5d6a4a749
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.json
@@ -0,0 +1,382 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "persistent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "1007+f+app+++system.gaiamobile.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++Users+joe+c+++index.html",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "moz-safe-about+home",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "https+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++Users+joe+index.html",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++localhost",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++c++",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++c++Users+joe+index.html",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++c++Users+joe+",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++127.0.0.1",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++++index.html",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++www.mozilla.org+8080",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "moz-safe-about+++home",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "resource+++fx-share-addon-at-mozilla-dot-org-fx-share-addon-data",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "indexeddb+++fx-devtools",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "https+++www.mozilla.org+8080",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "file++++Users+joe+",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              {
+                "name": "1007+f+app+++system.gaiamobile.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++localhost",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++localhost+82",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              { "name": "http+++localhost+81", "dir": true }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "file++++Users+joe+c+++index.html",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "https+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++Users+joe+index.html",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++localhost",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++c++",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++c++Users+joe+index.html",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++c++Users+joe+",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++127.0.0.1",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++++index.html",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org+8080",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "https+++www.mozilla.org+8080",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "file++++Users+joe+",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++localhost",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++localhost+82",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++localhost+81",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-safe-about+home",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "resource+++fx-share-addon-at-mozilla-dot-org-fx-share-addon-data",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "indexeddb+++fx-devtools",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.zip b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.zip
new file mode 100644
index 0000000000..ab8c045be9
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/persistentStorageDirectory_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/test_localStorageArchive1upgrade.js b/dom/quota/test/xpcshell/upgrades/test_localStorageArchive1upgrade.js
new file mode 100644
index 0000000000..f697d9167e
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_localStorageArchive1upgrade.js
@@ -0,0 +1,65 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that local storage directories are removed
+ * during local storage archive upgrade from version 0 to version 1.
+ * See bug 1546305.
+ */
+
+async function testSteps() {
+  const lsDirs = [
+    "storage/default/http+++example.com/ls",
+    "storage/default/http+++localhost/ls",
+    "storage/default/http+++www.mozilla.org/ls",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains three initialized origin directories with local
+  // storage data, local storage archive, a script for origin initialization,
+  // the storage database and the web apps store database:
+  // - storage/default/https+++example.com
+  // - storage/default/https+++localhost
+  // - storage/default/https+++www.mozilla.org
+  // - storage/ls-archive.sqlite
+  // - create_db.js
+  // - storage.sqlite
+  // - webappsstore.sqlite
+  // The file create_db.js in the package was run locally (with a build that
+  // doesn't support local storage archive upgrades), specifically it was
+  // temporarily added to xpcshell.ini and then executed:
+  //   mach xpcshell-test --interactive dom/localstorage/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/temporary".
+  installPackage("localStorageArchive1upgrade_profile");
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(exists, "ls directory does exist");
+  }
+
+  request = init();
+  request = await requestFinished(request);
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(!exists, "ls directory doesn't exist");
+  }
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_localStorageArchive4upgrade.js b/dom/quota/test/xpcshell/upgrades/test_localStorageArchive4upgrade.js
new file mode 100644
index 0000000000..0b0fcfccd6
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_localStorageArchive4upgrade.js
@@ -0,0 +1,107 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that local storage directories are removed
+ * during local storage archive upgrade from version 3 to version 4.
+ * See bug 1549654.
+ */
+
+async function testSteps() {
+  const lsDirs = [
+    "storage/default/http+++localhost/ls",
+    "storage/default/http+++www.mozilla.org/ls",
+    "storage/default/http+++example.com/ls",
+  ];
+
+  const principalInfos = [
+    "http://localhost",
+    "http://www.mozilla.org",
+    "http://example.com",
+  ];
+
+  const data = [
+    { key: "foo0", value: "bar" },
+    { key: "foo1", value: "A" },
+    { key: "foo2", value: "A".repeat(100) },
+  ];
+
+  function getLocalStorage(principal) {
+    return Services.domStorageManager.createStorage(
+      null,
+      principal,
+      principal,
+      ""
+    );
+  }
+
+  info("Setting pref");
+
+  // xpcshell globals don't have associated clients in the Clients API sense, so
+  // we need to disable client validation so that this xpcshell test is allowed
+  // to use LocalStorage.
+  Services.prefs.setBoolPref("dom.storage.client_validation", false);
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains three initialized origin directories with local
+  // storage data, local storage archive, a script for origin initialization,
+  // the storage database and the web apps store database:
+  // - storage/default/https+++example.com
+  // - storage/default/https+++localhost
+  // - storage/default/https+++www.mozilla.org
+  // - storage/ls-archive.sqlite
+  // - create_db.js
+  // - storage.sqlite
+  // - webappsstore.sqlite
+  // The file create_db.js in the package was run locally (with a build with
+  // local storage archive version 3), specifically it was temporarily added to
+  // xpcshell.ini and then executed:
+  //   mach xpcshell-test --interactive dom/localstorage/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/temporary".
+  installPackage("localStorageArchive4upgrade_profile");
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(exists, "ls directory does exist");
+  }
+
+  request = init();
+  request = await requestFinished(request);
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(!exists, "ls directory doesn't exist");
+  }
+
+  info("Getting storages");
+
+  let storages = [];
+  for (let i = 0; i < principalInfos.length; i++) {
+    let storage = getLocalStorage(getPrincipal(principalInfos[i]));
+    storages.push(storage);
+  }
+
+  info("Verifying data");
+
+  for (let i = 0; i < storages.length; i++) {
+    is(storages[i].getItem(data[i].key), data[i].value, "Correct value");
+  }
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_localStorageArchiveDowngrade.js b/dom/quota/test/xpcshell/upgrades/test_localStorageArchiveDowngrade.js
new file mode 100644
index 0000000000..8ca46f01d5
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_localStorageArchiveDowngrade.js
@@ -0,0 +1,66 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that local storage directories are removed
+ * during local storage archive downgrade from any future version to current
+ * version. See bug 1546305.
+ */
+
+async function testSteps() {
+  const lsDirs = [
+    "storage/default/http+++example.com/ls",
+    "storage/default/http+++localhost/ls",
+    "storage/default/http+++www.mozilla.org/ls",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Installing package");
+
+  // The profile contains three initialized origin directories with local
+  // storage data, local storage archive, a script for origin initialization,
+  // the storage database and the web apps store database:
+  // - storage/default/https+++example.com
+  // - storage/default/https+++localhost
+  // - storage/default/https+++www.mozilla.org
+  // - storage/ls-archive.sqlite
+  // - create_db.js
+  // - storage.sqlite
+  // - webappsstore.sqlite
+  // The file create_db.js in the package was run locally (with a build that
+  // supports local storage archive upgrades and local storage archive version
+  // set to max integer), specifically it was temporarily added to xpcshell.ini
+  // and then executed:
+  //   mach xpcshell-test --interactive dom/localstorage/test/xpcshell/create_db.js
+  // Note: to make it become the profile in the test, additional manual steps
+  // are needed.
+  // 1. Remove the folder "storage/temporary".
+  installPackage("localStorageArchiveDowngrade_profile");
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(exists, "ls directory does exist");
+  }
+
+  request = init();
+  request = await requestFinished(request);
+
+  info("Checking ls dirs");
+
+  for (let lsDir of lsDirs) {
+    let dir = getRelativeFile(lsDir);
+
+    exists = dir.exists();
+    ok(!exists, "ls directory doesn't exist");
+  }
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeCacheFrom1.js b/dom/quota/test/xpcshell/upgrades/test_upgradeCacheFrom1.js
new file mode 100644
index 0000000000..e9424e20c6
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeCacheFrom1.js
@@ -0,0 +1,79 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify UpgradeCacheFrom1To2 method.
+ */
+
+async function testSteps() {
+  const packages = [
+    // Storage used prior FF 88 (cache version 1).
+    // The profile contains one initialized origin directory with simple
+    // database data, a script for origin initialization and the storage
+    // database:
+    // - storage/default/https+++www.mozilla.org^userContextId=1
+    // - create_db.js
+    // - storage.sqlite
+    // The file create_db.js in the package was run locally, specifically it was
+    // temporarily added to xpcshell.ini and then executed:
+    //   mach xpcshell-test dom/quota/test/xpcshell/upgrades/create_db.js
+    //   --interactive
+    // Note: to make it become the profile in the test, additional manual steps
+    // are needed.
+    // 1. Remove the folder "storage/temporary".
+    // 2. Remove the file "storage/ls-archive.sqlite".
+    "cacheVersion1_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+  const principal = getPrincipal("https://www.mozilla.org", {
+    userContextId: 1,
+  });
+  const originUsage = 100;
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing package");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  await requestFinished(request);
+
+  info("Getting origin usage");
+
+  request = getOriginUsage(principal, /* fromMemory */ true);
+  await requestFinished(request);
+
+  info("Verifying origin usage");
+
+  is(request.result.usage, originUsage, "Correct origin usage");
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromFlatOriginDirectories.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromFlatOriginDirectories.js
new file mode 100644
index 0000000000..f33ddac8ca
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromFlatOriginDirectories.js
@@ -0,0 +1,187 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// A flat origin directory is an origin directory with no sub directories for
+// quota clients. The upgrade was initially done lazily and an empty .metadata
+// file was used to indicate a successful upgrade.
+
+function* testSteps() {
+  const setups = [
+    {
+      packages: [
+        // Storage used prior FF 22 (indexedDB/ directory with flat origin
+        // directories).
+        // FF 26 renamed indexedDB/ to storage/persistent and the lazy upgrade
+        // of flat origin directories remained. There's a test for that below.
+        "indexedDBDirectory_flatOriginDirectories_profile",
+        "../indexedDBDirectory_shared",
+      ],
+      origins: [
+        {
+          oldPath: "indexedDB/1007+f+app+++system.gaiamobile.org",
+        },
+
+        {
+          oldPath: "indexedDB/1007+t+https+++developer.cdn.mozilla.net",
+        },
+
+        {
+          oldPath: "indexedDB/http+++www.mozilla.org",
+          newPath: "storage/default/http+++www.mozilla.org",
+          url: "http://www.mozilla.org",
+          persistence: "default",
+        },
+      ],
+    },
+
+    {
+      packages: [
+        // Storage used by FF 26-35 (storage/persistent/ directory with not yet
+        // upgraded flat origin directories).
+        // FF 36 renamed storage/persistent/ to storage/default/ and all not
+        // yet upgraded flat origin directories were upgraded. There's a
+        // separate test for that:
+        // test_upgradeFromPersistentStorageDirectory_upgradeOriginDirectories.
+        "persistentStorageDirectory_flatOriginDirectories_profile",
+        "../persistentStorageDirectory_shared",
+      ],
+      origins: [
+        {
+          oldPath: "storage/persistent/1007+f+app+++system.gaiamobile.org",
+        },
+
+        {
+          oldPath:
+            "storage/persistent/1007+t+https+++developer.cdn.mozilla.net",
+        },
+
+        {
+          oldPath: "storage/persistent/http+++www.mozilla.org",
+          newPath: "storage/default/http+++www.mozilla.org",
+          url: "http://www.mozilla.org",
+          persistence: "default",
+        },
+      ],
+    },
+  ];
+
+  const metadataFileName = ".metadata";
+
+  for (const setup of setups) {
+    clear(continueToNextStepSync);
+    yield undefined;
+
+    info("Verifying storage");
+
+    verifyStorage(setup.packages, "beforeInstall");
+
+    info("Installing packages");
+
+    installPackages(setup.packages);
+
+    info("Verifying storage");
+
+    verifyStorage(setup.packages, "afterInstall");
+
+    info("Checking origin directories");
+
+    for (const origin of setup.origins) {
+      let originDir = getRelativeFile(origin.oldPath);
+      let exists = originDir.exists();
+      ok(exists, "Origin directory does exist");
+
+      let idbDir = originDir.clone();
+      idbDir.append("idb");
+
+      exists = idbDir.exists();
+      ok(!exists, "idb directory doesn't exist");
+
+      let metadataFile = originDir.clone();
+      metadataFile.append(metadataFileName);
+
+      exists = metadataFile.exists();
+      ok(!exists, "Metadata file doesn't exist");
+
+      if (origin.newPath) {
+        originDir = getRelativeFile(origin.newPath);
+        exists = originDir.exists();
+        ok(!exists, "Origin directory doesn't exist");
+      }
+    }
+
+    info("Initializing");
+
+    let request = init(continueToNextStepSync);
+    yield undefined;
+
+    ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+    info("Verifying storage");
+
+    verifyStorage(setup.packages, "afterInit");
+
+    // TODO: Remove this block once temporary storage initialization is able to
+    //       ignore unknown directories.
+    getRelativeFile("storage/default/invalid+++example.com").remove(false);
+    try {
+      getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+    } catch (ex) {}
+
+    info("Checking origin directories");
+
+    for (const origin of setup.origins) {
+      let originDir = getRelativeFile(origin.oldPath);
+      let exists = originDir.exists();
+      ok(!exists, "Origin directory doesn't exist");
+
+      if (origin.newPath) {
+        originDir = getRelativeFile(origin.newPath);
+        exists = originDir.exists();
+        ok(exists, "Origin directory does exist");
+
+        let idbDir = originDir.clone();
+        idbDir.append("idb");
+
+        exists = idbDir.exists();
+        ok(exists, "idb directory does exist");
+
+        let metadataFile = originDir.clone();
+        metadataFile.append(metadataFileName);
+
+        exists = metadataFile.exists();
+        ok(exists, "Metadata file does exist");
+      }
+    }
+
+    info("Initializing temporary storage");
+
+    request = initTemporaryStorage(continueToNextStepSync);
+    yield undefined;
+
+    ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+    info("Initializing origins");
+
+    for (const origin of setup.origins) {
+      if (origin.newPath) {
+        info("Initializing origin");
+
+        let principal = getPrincipal(origin.url);
+        request = initTemporaryOrigin(
+          origin.persistence,
+          principal,
+          continueToNextStepSync
+        );
+        yield undefined;
+
+        ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+        ok(!request.result, "Origin directory wasn't created");
+      }
+    }
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory.js
new file mode 100644
index 0000000000..b1b0966d67
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory.js
@@ -0,0 +1,121 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify
+ * MaybeUpgradeFromIndexedDBDirectoryToPersistentStorageDirectory method.
+ */
+
+function* testSteps() {
+  const origins = [
+    {
+      oldPath: "indexedDB/http+++www.mozilla.org",
+      newPath: "storage/default/http+++www.mozilla.org",
+      url: "http://www.mozilla.org",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "indexedDB/1007+f+app+++system.gaiamobile.org",
+    },
+
+    {
+      oldPath: "indexedDB/1007+t+https+++developer.cdn.mozilla.net",
+    },
+  ];
+
+  const packages = [
+    // Storage used prior FF 26 (indexedDB/ directory).
+    "indexedDBDirectory_profile",
+    "../indexedDBDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing package");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    if (origin.newPath) {
+      originDir = getRelativeFile(origin.newPath);
+      exists = originDir.exists();
+      ok(!exists, "Origin directory doesn't exist");
+    }
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(!exists, "Origin directory doesn't exist");
+
+    if (origin.newPath) {
+      originDir = getRelativeFile(origin.newPath);
+      exists = originDir.exists();
+      ok(exists, "Origin directory does exist");
+    }
+  }
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    if (origin.newPath) {
+      info("Initializing origin");
+
+      let principal = getPrincipal(origin.url);
+      request = initTemporaryOrigin(
+        origin.persistence,
+        principal,
+        continueToNextStepSync
+      );
+      yield undefined;
+
+      ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+      ok(!request.result, "Origin directory wasn't created");
+    }
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory_removeOldDirectory.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory_removeOldDirectory.js
new file mode 100644
index 0000000000..a7beced885
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromIndexedDBDirectory_removeOldDirectory.js
@@ -0,0 +1,86 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that the old directory is removed in
+ * MaybeUpgradeFromIndexedDBDirectoryToPersistentStorageDirectory method.
+ */
+
+async function testSteps() {
+  const url = "http://www.mozilla.org";
+  const persistence = "default";
+
+  const packages = [
+    // Storage used by FF 26-35 (storage/persistent/ directory and re-created
+    // indexedDB directory by an older FF).
+    "indexedDBAndPersistentStorageDirectory_profile",
+    "../persistentStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking directories");
+
+  let indexedDBDir = getRelativeFile("indexedDB");
+  let exists = indexedDBDir.exists();
+  ok(exists, "IndexedDB directory does exist");
+
+  let persistentStorageDir = getRelativeFile("storage/persistent");
+  exists = persistentStorageDir.exists();
+  ok(exists, "Persistent storage directory does exist");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking directories");
+
+  indexedDBDir = getRelativeFile("indexedDB");
+  exists = indexedDBDir.exists();
+  ok(!exists, "IndexedDB directory doesn't exist");
+
+  // FF 36 renamed storage/persistent/ to storage/default/ so it can't exist
+  // either.
+  persistentStorageDir = getRelativeFile("storage/persistent");
+  exists = persistentStorageDir.exists();
+  ok(!exists, "Persistent storage directory doesn't exist");
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Initializing origin");
+
+  request = initTemporaryOrigin(persistence, getPrincipal(url));
+  await requestFinished(request);
+
+  ok(!request.result, "Origin directory wasn't created");
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory.js
new file mode 100644
index 0000000000..efac150067
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory.js
@@ -0,0 +1,378 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify
+ * MaybeUpgradeFromPersistentStorageDirectoryToDefaultStorageDirectory method.
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+function* testSteps() {
+  const origins = [
+    {
+      oldPath: "storage/persistent/1007+f+app+++system.gaiamobile.org",
+    },
+
+    {
+      oldPath: "storage/persistent/1007+t+https+++developer.cdn.mozilla.net",
+    },
+
+    {
+      oldPath: "storage/persistent/chrome",
+      newPath: "storage/permanent/chrome",
+      chrome: true,
+      persistence: "persistent",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++",
+      newPath: "storage/default/file++++",
+      url: "file:///",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++++index.html",
+      newPath: "storage/default/file++++++index.html",
+      url: "file:///+/index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++++index.html",
+      newPath: "storage/default/file++++++index.html",
+      url: "file://///index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++Users+joe+",
+      newPath: "storage/default/file++++Users+joe+",
+      url: "file:///Users/joe/",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++Users+joe+c+++index.html",
+      newPath: "storage/default/file++++Users+joe+c+++index.html",
+      url: "file:///Users/joe/c++/index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++Users+joe+c+++index.html",
+      newPath: "storage/default/file++++Users+joe+c+++index.html",
+      url: "file:///Users/joe/c///index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++Users+joe+index.html",
+      newPath: "storage/default/file++++Users+joe+index.html",
+      url: "file:///Users/joe/index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++c++",
+      newPath: "storage/default/file++++c++",
+      url: "file:///c:/",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++c++Users+joe+",
+      newPath: "storage/default/file++++c++Users+joe+",
+      url: "file:///c:/Users/joe/",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/file++++c++Users+joe+index.html",
+      newPath: "storage/default/file++++c++Users+joe+index.html",
+      url: "file:///c:/Users/joe/index.html",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/http+++127.0.0.1",
+      newPath: "storage/default/http+++127.0.0.1",
+      url: "http://127.0.0.1",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/http+++localhost",
+      newPath: "storage/default/http+++localhost",
+      url: "http://localhost",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/http+++www.mozilla.org",
+      newPath: "storage/default/http+++www.mozilla.org",
+      url: "http://www.mozilla.org",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/http+++www.mozilla.org+8080",
+      newPath: "storage/default/http+++www.mozilla.org+8080",
+      url: "http://www.mozilla.org:8080",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/https+++www.mozilla.org",
+      newPath: "storage/default/https+++www.mozilla.org",
+      url: "https://www.mozilla.org",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/https+++www.mozilla.org+8080",
+      newPath: "storage/default/https+++www.mozilla.org+8080",
+      url: "https://www.mozilla.org:8080",
+      persistence: "default",
+    },
+
+    {
+      oldPath: "storage/persistent/indexeddb+++fx-devtools",
+      newPath: "storage/permanent/indexeddb+++fx-devtools",
+      url: "indexeddb://fx-devtools",
+      persistence: "persistent",
+    },
+
+    {
+      oldPath: "storage/persistent/moz-safe-about+++home",
+    },
+
+    {
+      oldPath: "storage/persistent/moz-safe-about+home",
+      newPath: "storage/permanent/moz-safe-about+home",
+      url: "moz-safe-about:home",
+      persistence: "persistent",
+    },
+
+    {
+      oldPath:
+        "storage/persistent/resource+++fx-share-addon-at-mozilla-dot-org-fx-share-addon-data",
+      newPath:
+        "storage/permanent/resource+++fx-share-addon-at-mozilla-dot-org-fx-share-addon-data",
+      url: "resource://fx-share-addon-at-mozilla-dot-org-fx-share-addon-data",
+      persistence: "persistent",
+    },
+
+    {
+      oldPath: "storage/temporary/1007+f+app+++system.gaiamobile.org",
+    },
+
+    {
+      oldPath: "storage/temporary/1007+t+https+++developer.cdn.mozilla.net",
+    },
+
+    // The .metadata file was intentionally appended for this origin directory
+    // to test recovery from unfinished upgrades (some metadata files can be
+    // already upgraded).
+    {
+      oldPath: "storage/temporary/chrome",
+      newPath: "storage/temporary/chrome",
+      metadataUpgraded: true,
+      chrome: true,
+      persistence: "temporary",
+    },
+
+    {
+      oldPath: "storage/temporary/http+++localhost",
+      newPath: "storage/temporary/http+++localhost",
+      url: "http://localhost",
+      persistence: "temporary",
+    },
+
+    // The .metadata file was intentionally removed for this origin directory
+    // to test restoring during upgrade.
+    {
+      oldPath: "storage/temporary/http+++localhost+81",
+      newPath: "storage/temporary/http+++localhost+81",
+      metadataRemoved: true,
+      url: "http://localhost:81",
+      persistence: "temporary",
+    },
+
+    // The .metadata file was intentionally truncated for this origin directory
+    // to test restoring during upgrade.
+    {
+      oldPath: "storage/temporary/http+++localhost+82",
+      newPath: "storage/temporary/http+++localhost+82",
+      url: "http://localhost:82",
+      persistence: "temporary",
+    },
+  ];
+
+  const metadataFileName = ".metadata";
+
+  const packages = [
+    // Storage used by 26-35 (storage/persistent/ directory, tracked only
+    // timestamp in .metadata for persistent storage and isApp not tracked in
+    // .metadata for temporary storage).
+    "persistentStorageDirectory_profile",
+    "../persistentStorageDirectory_shared",
+  ];
+
+  let metadataBuffers = [];
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    if (origin.newPath) {
+      info("Reading out contents of metadata file");
+
+      let metadataFile = originDir.clone();
+      metadataFile.append(metadataFileName);
+
+      if (origin.metadataRemoved) {
+        metadataBuffers.push(new ArrayBuffer(0));
+      } else {
+        File.createFromNsIFile(metadataFile).then(grabArgAndContinueHandler);
+        let file = yield undefined;
+
+        let fileReader = new FileReader();
+        fileReader.onload = continueToNextStepSync;
+        fileReader.readAsArrayBuffer(file);
+
+        yield undefined;
+
+        metadataBuffers.push(fileReader.result);
+      }
+
+      if (origin.newPath != origin.oldPath) {
+        originDir = getRelativeFile(origin.newPath);
+        exists = originDir.exists();
+        ok(!exists, "Origin directory doesn't exist");
+      }
+    }
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    if (!origin.newPath || origin.newPath != origin.oldPath) {
+      let originDir = getRelativeFile(origin.oldPath);
+      let exists = originDir.exists();
+      ok(!exists, "Origin directory doesn't exist");
+    }
+
+    if (origin.newPath) {
+      let originDir = getRelativeFile(origin.newPath);
+      let exists = originDir.exists();
+      ok(exists, "Origin directory does exist");
+
+      info("Reading out contents of metadata file");
+
+      let metadataFile = originDir.clone();
+      metadataFile.append(metadataFileName);
+
+      File.createFromNsIFile(metadataFile).then(grabArgAndContinueHandler);
+      let file = yield undefined;
+
+      let fileReader = new FileReader();
+      fileReader.onload = continueToNextStepSync;
+      fileReader.readAsArrayBuffer(file);
+
+      yield undefined;
+
+      let metadataBuffer = fileReader.result;
+
+      info("Verifying blobs differ");
+
+      if (origin.metadataUpgraded) {
+        ok(
+          compareBuffers(metadataBuffer, metadataBuffers.shift()),
+          "Metadata doesn't differ"
+        );
+      } else {
+        ok(
+          !compareBuffers(metadataBuffer, metadataBuffers.shift()),
+          "Metadata differ"
+        );
+      }
+    }
+  }
+
+  info("Initializing");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    if (origin.newPath) {
+      info("Initializing origin");
+
+      let principal;
+      if (origin.chrome) {
+        principal = getCurrentPrincipal();
+      } else {
+        principal = getPrincipal(origin.url);
+      }
+
+      if (origin.persistence == "persistent") {
+        request = initPersistentOrigin(principal, continueToNextStepSync);
+      } else {
+        request = initTemporaryOrigin(
+          origin.persistence,
+          principal,
+          continueToNextStepSync
+        );
+      }
+      yield undefined;
+
+      ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+      ok(!request.result, "Origin directory wasn't created");
+    }
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_removeOldDirectory.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_removeOldDirectory.js
new file mode 100644
index 0000000000..e9f1ae2291
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_removeOldDirectory.js
@@ -0,0 +1,102 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify that the old directory is removed in
+ * MaybeUpgradeFromPersistentStorageDirectoryToDefaultStorageDirectory method.
+ */
+
+async function testSteps() {
+  const url = "http://www.mozilla.org";
+  const persistence = "default";
+  const lastAccessed = 0x0005330925e07841;
+
+  const packages = [
+    // Storage used by FF 36-48 (storage/default/ directory and re-created
+    // storage/persistent/ directory by an older FF).
+    "persistentAndDefaultStorageDirectory_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking directories");
+
+  let persistentStorageDir = getRelativeFile("storage/persistent");
+  let exists = persistentStorageDir.exists();
+  ok(exists, "Persistent storage directory does exist");
+
+  let defaultStorageDir = getRelativeFile("storage/default");
+  exists = defaultStorageDir.exists();
+  ok(exists, "Default storage directory does exist");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization and getting
+  //       usage is able to ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/permanent/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking directories");
+
+  persistentStorageDir = getRelativeFile("storage/persistent");
+  exists = persistentStorageDir.exists();
+  ok(!exists, "Persistent storage directory doesn't exist");
+
+  defaultStorageDir = getRelativeFile("storage/default");
+  exists = defaultStorageDir.exists();
+  ok(exists, "Default storage directory does exist");
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage();
+  await requestFinished(request);
+
+  info("Initializing origin");
+
+  request = initTemporaryOrigin(persistence, getPrincipal(url));
+  await requestFinished(request);
+
+  ok(!request.result, "Origin directory wasn't created");
+
+  info("Getting usage");
+
+  request = getUsage(function() {}, /* getAll */ true);
+  await requestFinished(request);
+
+  info("Verifying result");
+
+  const result = request.result;
+  is(result.length, 1, "Correct number of usage results");
+
+  info("Verifying usage result");
+
+  const usageResult = result[0];
+  ok(usageResult.origin == url, "Origin equals");
+  ok(usageResult.lastAccessed == lastAccessed, "LastAccessed equals");
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_upgradeOriginDirectories.js b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_upgradeOriginDirectories.js
new file mode 100644
index 0000000000..cac8ec3b16
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeFromPersistentStorageDirectory_upgradeOriginDirectories.js
@@ -0,0 +1,162 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+function* testSteps() {
+  const origins = [
+    {
+      oldPath: "storage/persistent/1007+f+app+++system.gaiamobile.org",
+      upgraded: true,
+    },
+
+    {
+      oldPath: "storage/persistent/1007+t+https+++developer.cdn.mozilla.net",
+      upgraded: true,
+    },
+
+    {
+      oldPath: "storage/persistent/http+++www.mozilla.org",
+      newPath: "storage/default/http+++www.mozilla.org",
+      url: "http://www.mozilla.org",
+      persistence: "default",
+      upgraded: true,
+    },
+    {
+      oldPath: "storage/persistent/http+++www.mozilla.org+8080",
+      newPath: "storage/default/http+++www.mozilla.org+8080",
+      url: "http://www.mozilla.org:8080",
+      persistence: "default",
+    },
+  ];
+
+  const metadataFileName = ".metadata";
+
+  const packages = [
+    // Storage used by FF 26-35 (storage/persistent/ directory with already
+    // upgraded origin directories and not yet upgraded flat origin
+    // directories).
+    "persistentStorageDirectory_originDirectories_profile",
+    "../persistentStorageDirectory_shared",
+  ];
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking origin directories");
+
+  for (const origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    let idbDir = originDir.clone();
+    idbDir.append("idb");
+
+    exists = idbDir.exists();
+    if (origin.upgraded) {
+      ok(exists, "idb directory does exist");
+    } else {
+      ok(!exists, "idb directory doesn't exist");
+    }
+
+    let metadataFile = originDir.clone();
+    metadataFile.append(metadataFileName);
+
+    exists = metadataFile.exists();
+    if (origin.upgraded) {
+      ok(exists, "Metadata file does exist");
+    } else {
+      ok(!exists, "Metadata file doesn't exist");
+    }
+
+    if (origin.newPath) {
+      originDir = getRelativeFile(origin.newPath);
+      exists = originDir.exists();
+      ok(!exists, "Origin directory doesn't exist");
+    }
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization and getting
+  //       usage is able to ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking origin directories");
+
+  for (const origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(!exists, "Origin directory doesn't exist");
+
+    if (origin.newPath) {
+      originDir = getRelativeFile(origin.newPath);
+      exists = originDir.exists();
+      ok(exists, "Origin directory does exist");
+
+      let idbDir = originDir.clone();
+      idbDir.append("idb");
+
+      exists = idbDir.exists();
+      ok(exists, "idb directory does exist");
+
+      let metadataFile = originDir.clone();
+      metadataFile.append(metadataFileName);
+
+      exists = metadataFile.exists();
+      ok(exists, "Metadata file does exist");
+    }
+  }
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    if (origin.newPath) {
+      info("Initializing origin");
+
+      let principal = getPrincipal(origin.url);
+      request = initTemporaryOrigin(
+        origin.persistence,
+        principal,
+        continueToNextStepSync
+      );
+      yield undefined;
+
+      ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+      ok(!request.result, "Origin directory wasn't created");
+    }
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom0_0.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom0_0.js
new file mode 100644
index 0000000000..bd6a010cf8
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom0_0.js
@@ -0,0 +1,158 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify UpgradeStorageFrom0_0To1_0 method.
+ */
+
+function* testSteps() {
+  const origins = [
+    {
+      path: "storage/default/1007+f+app+++system.gaiamobile.org",
+      obsolete: true,
+    },
+
+    {
+      path: "storage/default/1007+t+https+++developer.cdn.mozilla.net",
+      obsolete: true,
+    },
+
+    {
+      path: "storage/default/http+++www.mozilla.org",
+      obsolete: false,
+      url: "http://www.mozilla.org",
+      persistence: "default",
+    },
+  ];
+
+  const storageFileName = "storage.sqlite";
+  const metadataFileName = ".metadata";
+  const metadata2FileName = ".metadata-v2";
+
+  const packages = [
+    // Storage used by FF 36-48 (storage/default/ directory, but no
+    // storage.sqlite and no .metadata-v2 files).
+    "version0_0_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking storage file");
+
+  let storageFile = getRelativeFile(storageFileName);
+
+  let exists = storageFile.exists();
+  ok(!exists, "Storage file doesn't exist");
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.path);
+
+    exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    let metadataFile = originDir.clone();
+    metadataFile.append(metadataFileName);
+
+    exists = metadataFile.exists();
+    ok(exists, "Metadata file does exist");
+
+    let metadata2File = originDir.clone();
+    metadata2File.append(metadata2FileName);
+
+    exists = metadata2File.exists();
+    ok(!exists, "Metadata file doesn't exist");
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  exists = storageFile.exists();
+  ok(exists, "Storage file does exist");
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.path);
+
+    exists = originDir.exists();
+    if (origin.obsolete) {
+      ok(!exists, "Origin directory doesn't exist");
+    } else {
+      ok(exists, "Origin directory does exist");
+
+      let metadataFile = originDir.clone();
+      metadataFile.append(metadataFileName);
+
+      exists = metadataFile.exists();
+      ok(exists, "Metadata file does exist");
+
+      let metadata2File = originDir.clone();
+      metadata2File.append(metadata2FileName);
+
+      exists = metadata2File.exists();
+      ok(exists, "Metadata file does exist");
+    }
+  }
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    if (!origin.obsolete) {
+      info("Initializing origin");
+
+      let principal = getPrincipal(origin.url);
+      request = initTemporaryOrigin(
+        origin.persistence,
+        principal,
+        continueToNextStepSync
+      );
+      yield undefined;
+
+      ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+      ok(!request.result, "Origin directory wasn't created");
+    }
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_idb.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_idb.js
new file mode 100644
index 0000000000..34508f85e8
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_idb.js
@@ -0,0 +1,43 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify indexedDB::QuotaClient::UpgradeStorageFrom1_0To2_0
+ * method.
+ */
+
+async function testSteps() {
+  const packages = [
+    // Storage used by FF 49-54 (storage version 1.0 with idb directory).
+    "version1_0_idb_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Initializing");
+
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeAppsData.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeAppsData.js
new file mode 100644
index 0000000000..17946ffff5
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeAppsData.js
@@ -0,0 +1,101 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify MaybeRemoveAppsData method.
+ */
+
+function* testSteps() {
+  const origins = [
+    {
+      path: "storage/default/http+++www.mozilla.org",
+      obsolete: false,
+    },
+
+    {
+      path: "storage/default/app+++system.gaiamobile.org^appId=1007",
+      obsolete: true,
+    },
+
+    {
+      path:
+        "storage/default/https+++developer.cdn.mozilla.net^appId=1007&inBrowser=1",
+      obsolete: true,
+    },
+  ];
+
+  const packages = [
+    // Storage used by FF 49-54 (storage version 1.0 with apps data).
+    "version1_0_appsData_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.path);
+
+    let exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once getting usage is able to ignore unknown
+  //       directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/permanent/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.path);
+
+    let exists = originDir.exists();
+    if (origin.obsolete) {
+      ok(!exists, "Origin directory doesn't exist");
+    } else {
+      ok(exists, "Origin directory does exist");
+    }
+  }
+
+  info("Getting usage");
+
+  getUsage(grabResultAndContinueHandler, /* getAll */ true);
+  let result = yield undefined;
+
+  info("Verifying result");
+
+  is(result.length, 1, "Correct number of usage results");
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeMorgueDirectory.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeMorgueDirectory.js
new file mode 100644
index 0000000000..b37d00bbf8
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_removeMorgueDirectory.js
@@ -0,0 +1,60 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify MaybeRemoveMorgueDirectory method.
+ */
+
+function* testSteps() {
+  const morgueFile = "storage/default/http+++example.com/morgue";
+
+  const packages = [
+    // Storage used by FF 49-54 (storage version 1.0 with morgue directory).
+    "version1_0_morgueDirectory_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking morgue file");
+
+  let file = getRelativeFile(morgueFile);
+
+  let exists = file.exists();
+  ok(exists, "Morgue file does exist");
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  info("Checking morgue file");
+
+  exists = file.exists();
+  ok(!exists, "Morgue file doesn't exist");
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_stripObsoleteOriginAttributes.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_stripObsoleteOriginAttributes.js
new file mode 100644
index 0000000000..407a04c1f8
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom1_0_stripObsoleteOriginAttributes.js
@@ -0,0 +1,179 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify MaybeStripObsoleteOriginAttributes method.
+ */
+
+loadScript("dom/quota/test/common/file.js");
+
+function* testSteps() {
+  const origins = [
+    {
+      oldPath:
+        "storage/permanent/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+      newPath:
+        "storage/permanent/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+      url: "moz-extension://8ea6d31b-917c-431f-a204-15b95e904d4f",
+      persistence: "persistent",
+    },
+
+    {
+      oldPath:
+        "storage/temporary/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+      newPath:
+        "storage/temporary/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+      url: "moz-extension://8ea6d31b-917c-431f-a204-15b95e904d4f",
+      persistence: "temporary",
+    },
+
+    {
+      oldPath:
+        "storage/default/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+      newPath:
+        "storage/default/moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+      url: "moz-extension://8ea6d31b-917c-431f-a204-15b95e904d4f",
+      persistence: "default",
+    },
+  ];
+
+  const metadataFileName = ".metadata-v2";
+
+  const packages = [
+    // Storage used by FF 49-54 (storage version 1.0 with obsolete origin
+    // attributes).
+    "version1_0_obsoleteOriginAttributes_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  let metadataBuffers = [];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    info("Reading out contents of metadata file");
+
+    let metadataFile = originDir.clone();
+    metadataFile.append(metadataFileName);
+
+    File.createFromNsIFile(metadataFile).then(grabArgAndContinueHandler);
+    let file = yield undefined;
+
+    let fileReader = new FileReader();
+    fileReader.onload = continueToNextStepSync;
+    fileReader.readAsArrayBuffer(file);
+
+    yield undefined;
+
+    metadataBuffers.push(fileReader.result);
+
+    originDir = getRelativeFile(origin.newPath);
+    exists = originDir.exists();
+    ok(!exists, "Origin directory doesn't exist");
+  }
+
+  info("Initializing");
+
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  // TODO: Remove this block once temporary storage initialization is able to
+  //       ignore unknown directories.
+  getRelativeFile("storage/default/invalid+++example.com").remove(false);
+  getRelativeFile("storage/temporary/invalid+++example.com").remove(false);
+
+  info("Checking origin directories");
+
+  for (let origin of origins) {
+    let originDir = getRelativeFile(origin.oldPath);
+    let exists = originDir.exists();
+    ok(!exists, "Origin directory doesn't exist");
+
+    originDir = getRelativeFile(origin.newPath);
+    exists = originDir.exists();
+    ok(exists, "Origin directory does exist");
+
+    info("Reading out contents of metadata file");
+
+    let metadataFile = originDir.clone();
+    metadataFile.append(metadataFileName);
+
+    File.createFromNsIFile(metadataFile).then(grabArgAndContinueHandler);
+    let file = yield undefined;
+
+    let fileReader = new FileReader();
+    fileReader.onload = continueToNextStepSync;
+    fileReader.readAsArrayBuffer(file);
+
+    yield undefined;
+
+    let metadataBuffer = fileReader.result;
+
+    info("Verifying blobs differ");
+
+    ok(
+      !compareBuffers(metadataBuffer, metadataBuffers.shift()),
+      "Metadata differ"
+    );
+  }
+
+  info("Initializing temporary storage");
+
+  request = initTemporaryStorage(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Initializing origins");
+
+  for (const origin of origins) {
+    info("Initializing origin");
+
+    let principal = getPrincipal(origin.url);
+    if (origin.persistence == "persistent") {
+      request = initPersistentOrigin(principal, continueToNextStepSync);
+    } else {
+      request = initTemporaryOrigin(
+        origin.persistence,
+        principal,
+        continueToNextStepSync
+      );
+    }
+    yield undefined;
+
+    ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+    ok(!request.result, "Origin directory wasn't created");
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_0.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_0.js
new file mode 100644
index 0000000000..55edfa6055
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_0.js
@@ -0,0 +1,97 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify UpgradeStorageFrom2_0To2_1 method.
+ */
+
+function* testSteps() {
+  const origins = [
+    "storage/default/chrome/",
+    "storage/default/http+++www.mozilla.org/",
+  ];
+  const paddingFilePath = "cache/.padding";
+
+  const packages = [
+    // Storage used by FF 55-56 (storage version 2.0).
+    // The profile contains two cache storages:
+    // - storage/default/chrome/cache,
+    // - storage/default/http+++www.mozilla.org/cache
+    // The file create_cache.js in the package was run locally, specifically it
+    // was temporarily added to xpcshell.ini and then executed:
+    //   mach xpcshell-test --interactive dom/quota/test/xpcshell/create_cache.js
+    // Note: it only creates the directory "storage/default/chrome/cache".
+    // To make it become the profile in the test, two more manual steps are
+    // needed.
+    // 1. Remove the folder "storage/temporary".
+    // 2. Copy the content under the "storage/default/chrome" to
+    //    "storage/default/http+++www.mozilla.org".
+    // 3. Manually create an asmjs folder under the
+    //    "storage/default/http+++www.mozilla.org/".
+    "version2_0_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  clear(continueToNextStepSync);
+  yield undefined;
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking padding files before upgrade (storage version 2.0)");
+
+  for (let origin of origins) {
+    let paddingFile = getRelativeFile(origin + paddingFilePath);
+    let exists = paddingFile.exists();
+    ok(!exists, "Padding file doesn't exist");
+  }
+
+  info("Initializing");
+
+  // Initialize to trigger storage upgrade from version 2.0.
+  let request = init(continueToNextStepSync);
+  yield undefined;
+
+  ok(request.resultCode == NS_OK, "Initialization succeeded");
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  info("Checking padding files after upgrade");
+
+  for (let origin of origins) {
+    let paddingFile = getRelativeFile(origin + paddingFilePath);
+    let exists = paddingFile.exists();
+    ok(exists, "Padding file does exist");
+
+    info("Reading out contents of padding file");
+
+    File.createFromNsIFile(paddingFile).then(grabArgAndContinueHandler);
+    let domFile = yield undefined;
+
+    let fileReader = new FileReader();
+    fileReader.onload = continueToNextStepSync;
+    fileReader.readAsArrayBuffer(domFile);
+    yield undefined;
+
+    let paddingFileInfo = new Float64Array(fileReader.result);
+    ok(paddingFileInfo.length == 1, "Padding file does take 64 bytes.");
+    ok(paddingFileInfo[0] == 0, "Padding size does default to zero.");
+  }
+
+  finishTest();
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_1.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_1.js
new file mode 100644
index 0000000000..eed7ed21d5
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_1.js
@@ -0,0 +1,85 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify UpgradeStorageFrom2_1To2_2 method (removal of
+ * obsolete origins, deprecated clients and unknown temporary files).
+ */
+
+async function testSteps() {
+  const filePaths = [
+    // Obsolete origins:
+    "storage/default/chrome+++content+browser.xul",
+
+    "storage/default/moz-safe-about+++home",
+
+    // TODO: These three origins don't belong here! They were added one release
+    //       later and the origin parser was fixed to handle these origins one
+    //       release later as well, so users which already upgraded to 2.2 may
+    //       still have issues related to these origins!
+    "storage/default/about+home+1",
+
+    "storage/default/about+home+1+q",
+
+    // about:reader?url=xxx (before bug 1422456)
+    "storage/default/about+reader+url=https%3A%2F%2Fexample.com",
+
+    // Deprecated client:
+    "storage/default/https+++example.com/asmjs",
+
+    // Unknown temporary file:
+    "storage/default/https+++example.com/idb/UUID123.tmp",
+  ];
+
+  const packages = [
+    // Storage used by FF 57-67 (storage version 2.1 with obsolete origins, a
+    // deprecated client and an unknown temporary file).
+    "version2_1_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  info("Checking files and directories before upgrade (storage version 2.1)");
+
+  for (const filePath of filePaths) {
+    let file = getRelativeFile(filePath);
+    let exists = file.exists();
+    ok(exists, "File or directory does exist");
+  }
+
+  info("Initializing");
+
+  // Initialize to trigger storage upgrade from version 2.1
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  info("Checking files and directories after upgrade");
+
+  for (const filePath of filePaths) {
+    let file = getRelativeFile(filePath);
+    let exists = file.exists();
+    ok(!exists, "File or directory does not exist");
+  }
+}
diff --git a/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_2.js b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_2.js
new file mode 100644
index 0000000000..8f41c05b49
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/test_upgradeStorageFrom2_2.js
@@ -0,0 +1,64 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/**
+ * This test is mainly to verify UpgradeStorageFrom2_2To2_3 method.
+ */
+
+async function testSteps() {
+  const packages = [
+    // Storage used by FF 68-69 (storage version 2.2).
+    "version2_2_profile",
+    "../defaultStorageDirectory_shared",
+  ];
+
+  function verifyDatabaseTable(shouldExist) {
+    let file = getRelativeFile("storage.sqlite");
+    let conn = Services.storage.openUnsharedDatabase(file);
+
+    let exists = conn.tableExists("database");
+    if (shouldExist) {
+      ok(exists, "Database table does exist");
+    } else {
+      ok(!exists, "Database table does not exist");
+    }
+
+    conn.close();
+  }
+
+  info("Clearing");
+
+  let request = clear();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "beforeInstall");
+
+  info("Installing packages");
+
+  installPackages(packages);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInstall");
+
+  verifyDatabaseTable(/* shouldExist */ false);
+
+  info("Initializing");
+
+  // Initialize to trigger storage upgrade from version 2.2
+  request = init();
+  await requestFinished(request);
+
+  info("Verifying storage");
+
+  verifyStorage(packages, "afterInit");
+
+  request = reset();
+  await requestFinished(request);
+
+  verifyDatabaseTable(/* shouldExist */ true);
+}
diff --git a/dom/quota/test/xpcshell/upgrades/version0_0_profile.json b/dom/quota/test/xpcshell/upgrades/version0_0_profile.json
new file mode 100644
index 0000000000..05c0d27fe3
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version0_0_profile.json
@@ -0,0 +1,88 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "1007+f+app+++system.gaiamobile.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "1007+t+https+++developer.cdn.mozilla.org",
+                "dir": true,
+                "entries": [{ "name": ".metadata", "dir": false }]
+              },
+              {
+                "name": "https+++developer.cdn.mozilla.org",
+                "dir": true
+              }
+            ]
+          }
+        ]
+      }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "todo": "This shouldn't exist, it regressed after accidental changes done in bug 1320404",
+                "name": "https+++developer.cdn.mozilla.net",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "https+++developer.cdn.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version0_0_profile.zip b/dom/quota/test/xpcshell/upgrades/version0_0_profile.zip
new file mode 100644
index 0000000000..5ef577191c
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version0_0_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.json b/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.json
new file mode 100644
index 0000000000..88f5d5dcee
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.json
@@ -0,0 +1,72 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "app+++system.gaiamobile.org^appId=1007",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "https+++developer.cdn.mozilla.net^appId=1007&inBrowser=1",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.zip b/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.zip
new file mode 100644
index 0000000000..582edb43af
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_appsData_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.json b/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.json
new file mode 100644
index 0000000000..a8fb8b2260
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.json
@@ -0,0 +1,73 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-safe-about+home",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "idb",
+                    "dir": true,
+                    "entries": [
+                      { "name": "631132235dGb", "dir": true },
+                      { "name": "631132235dGb.files", "dir": true },
+                      { "name": "631132235dGb.sqlite", "dir": false }
+                    ]
+                  },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir":false }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-safe-about+home",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "idb",
+                    "dir": true,
+                    "entries": [
+                      { "name": "631132235dGb.files", "dir": true },
+                      { "name": "631132235dGb.sqlite", "dir": false }
+                    ]
+                  },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir":false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.zip b/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.zip
new file mode 100644
index 0000000000..8abfae79c2
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_idb_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.json b/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.json
new file mode 100644
index 0000000000..855f7846bc
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.json
@@ -0,0 +1,57 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++example.com",
+                "dir": true,
+                "entries": [
+                  { "name": "morgue", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "http+++example.com",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.zip b/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.zip
new file mode 100644
index 0000000000..88543784ec
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_morgueDirectory_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.json b/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.json
new file mode 100644
index 0000000000..071c4413f4
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.json
@@ -0,0 +1,112 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f^addonId=indexedDB-test%40kmaglione.mozilla.com",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "permanent",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          {
+            "name": "temporary",
+            "dir": true,
+            "entries": [
+              {
+                "name": "moz-extension+++8ea6d31b-917c-431f-a204-15b95e904d4f",
+                "dir": true,
+                "entries": [
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.zip b/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.zip
new file mode 100644
index 0000000000..2b4125edf9
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version1_0_obsoleteOriginAttributes_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version2_0_profile.json b/dom/quota/test/xpcshell/upgrades/version2_0_profile.json
new file mode 100644
index 0000000000..04ad73eae3
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_0_profile.json
@@ -0,0 +1,105 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "cache",
+                    "dir": true,
+                    "entries": [
+                      { "name": "morgue", "dir": true },
+                      { "name": "caches.sqlite", "dir": false }
+                    ]
+                  },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  { "name": "asmjs", "dir": true },
+                  {
+                    "name": "cache",
+                    "dir": true,
+                    "entries": [
+                      { "name": "morgue", "dir": true },
+                      { "name": "caches.sqlite", "dir": false }
+                    ]
+                  }
+                ]
+              }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "chrome",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "cache",
+                    "dir": true,
+                    "entries": [
+                      { "name": "morgue", "dir": true },
+                      { "name": ".padding", "dir": false },
+                      { "name": "caches.sqlite", "dir": false }
+                    ]
+                  },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              },
+              {
+                "name": "http+++www.mozilla.org",
+                "dir": true,
+                "entries": [
+                  {
+                    "name": "cache",
+                    "dir": true,
+                    "entries": [
+                      { "name": "morgue", "dir": true },
+                      { "name": ".padding", "dir": false },
+                      { "name": "caches.sqlite", "dir": false }
+                    ]
+                  },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version2_0_profile.zip b/dom/quota/test/xpcshell/upgrades/version2_0_profile.zip
new file mode 100644
index 0000000000..c140df56e4
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_0_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version2_1_profile.json b/dom/quota/test/xpcshell/upgrades/version2_1_profile.json
new file mode 100644
index 0000000000..a7866d1123
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_1_profile.json
@@ -0,0 +1,69 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              { "name": "about+home+1", "dir": true },
+              { "name": "about+home+1+q", "dir": true },
+              {
+                "name": "about+reader+url=https%3A%2F%2Fexample.com",
+                "dir": true
+              },
+              { "name": "chrome+++content+browser.xul", "dir": true },
+              {
+                "name": "https+++example.com",
+                "dir": true,
+                "entries": [
+                  { "name": "asmjs", "dir": true },
+                  {
+                    "name": "idb",
+                    "dir": true,
+                    "entries": [{ "name": "UUID123.tmp", "dir": false }]
+                  }
+                ]
+              },
+              { "name": "moz-safe-about+++home", "dir": true }
+            ]
+          }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [
+          {
+            "name": "default",
+            "dir": true,
+            "entries": [
+              {
+                "name": "https+++example.com",
+                "dir": true,
+                "entries": [
+                  { "name": "idb", "dir": true },
+                  { "name": ".metadata", "dir": false },
+                  { "name": ".metadata-v2", "dir": false }
+                ]
+              }
+            ]
+          },
+          { "name": "ls-archive.sqlite", "dir": false }
+        ]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version2_1_profile.zip b/dom/quota/test/xpcshell/upgrades/version2_1_profile.zip
new file mode 100644
index 0000000000..908dac7058
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_1_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/version2_2_profile.json b/dom/quota/test/xpcshell/upgrades/version2_2_profile.json
new file mode 100644
index 0000000000..4b7265e3b4
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_2_profile.json
@@ -0,0 +1,18 @@
+[
+  { "key": "beforeInstall", "entries": [] },
+  {
+    "key": "afterInstall",
+    "entries": [{ "name": "storage.sqlite", "dir": false }]
+  },
+  {
+    "key": "afterInit",
+    "entries": [
+      {
+        "name": "storage",
+        "dir": true,
+        "entries": [{ "name": "ls-archive.sqlite", "dir": false }]
+      },
+      { "name": "storage.sqlite", "dir": false }
+    ]
+  }
+]
diff --git a/dom/quota/test/xpcshell/upgrades/version2_2_profile.zip b/dom/quota/test/xpcshell/upgrades/version2_2_profile.zip
new file mode 100644
index 0000000000..b6ae7e7d76
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/version2_2_profile.zip
diff --git a/dom/quota/test/xpcshell/upgrades/xpcshell.ini b/dom/quota/test/xpcshell/upgrades/xpcshell.ini
new file mode 100644
index 0000000000..8698e4bff4
--- /dev/null
+++ b/dom/quota/test/xpcshell/upgrades/xpcshell.ini
@@ -0,0 +1,61 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+[DEFAULT]
+head = head.js
+support-files =
+  cacheVersion1_profile.json
+  cacheVersion1_profile.zip
+  indexedDBAndPersistentStorageDirectory_profile.json
+  indexedDBAndPersistentStorageDirectory_profile.zip
+  indexedDBDirectory_flatOriginDirectories_profile.json
+  indexedDBDirectory_flatOriginDirectories_profile.zip
+  indexedDBDirectory_profile.json
+  indexedDBDirectory_profile.zip
+  localStorageArchive1upgrade_profile.zip
+  localStorageArchive4upgrade_profile.zip
+  localStorageArchiveDowngrade_profile.zip
+  persistentAndDefaultStorageDirectory_profile.json
+  persistentAndDefaultStorageDirectory_profile.zip
+  persistentStorageDirectory_flatOriginDirectories_profile.json
+  persistentStorageDirectory_flatOriginDirectories_profile.zip
+  persistentStorageDirectory_originDirectories_profile.json
+  persistentStorageDirectory_originDirectories_profile.zip
+  persistentStorageDirectory_profile.json
+  persistentStorageDirectory_profile.zip
+  version0_0_profile.json
+  version0_0_profile.zip
+  version1_0_appsData_profile.json
+  version1_0_appsData_profile.zip
+  version1_0_idb_profile.json
+  version1_0_idb_profile.zip
+  version1_0_morgueDirectory_profile.json
+  version1_0_morgueDirectory_profile.zip
+  version1_0_obsoleteOriginAttributes_profile.json
+  version1_0_obsoleteOriginAttributes_profile.zip
+  version2_0_profile.json
+  version2_0_profile.zip
+  version2_1_profile.json
+  version2_1_profile.zip
+  version2_2_profile.json
+  version2_2_profile.zip
+
+[test_localStorageArchive1upgrade.js]
+[test_localStorageArchive4upgrade.js]
+[test_localStorageArchiveDowngrade.js]
+[test_upgradeCacheFrom1.js]
+[test_upgradeFromFlatOriginDirectories.js]
+[test_upgradeFromIndexedDBDirectory.js]
+[test_upgradeFromIndexedDBDirectory_removeOldDirectory.js]
+[test_upgradeFromPersistentStorageDirectory.js]
+[test_upgradeFromPersistentStorageDirectory_removeOldDirectory.js]
+[test_upgradeFromPersistentStorageDirectory_upgradeOriginDirectories.js]
+[test_upgradeStorageFrom0_0.js]
+[test_upgradeStorageFrom1_0_idb.js]
+[test_upgradeStorageFrom1_0_removeAppsData.js]
+[test_upgradeStorageFrom1_0_removeMorgueDirectory.js]
+[test_upgradeStorageFrom1_0_stripObsoleteOriginAttributes.js]
+[test_upgradeStorageFrom2_0.js]
+[test_upgradeStorageFrom2_1.js]
+[test_upgradeStorageFrom2_2.js]
diff --git a/dom/quota/test/xpcshell/xpcshell.ini b/dom/quota/test/xpcshell/xpcshell.ini
new file mode 100644
index 0000000000..2b85faed16
--- /dev/null
+++ b/dom/quota/test/xpcshell/xpcshell.ini
@@ -0,0 +1,61 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+[DEFAULT]
+head = head.js
+tags = condprof
+support-files =
+  basics_profile.zip
+  clearStoragesForPrincipal_profile.zip
+  createLocalStorage_profile.zip
+  defaultStorageDirectory_shared.json
+  defaultStorageDirectory_shared.zip
+  getUsage_profile.zip
+  groupMismatch_profile.zip
+  indexedDBDirectory_shared.json
+  indexedDBDirectory_shared.zip
+  originMismatch_profile.json
+  originMismatch_profile.zip
+  persistentStorageDirectory_shared.json
+  persistentStorageDirectory_shared.zip
+  removeLocalStorage1_profile.zip
+  removeLocalStorage2_profile.zip
+  tempMetadataCleanup_profile.zip
+  unknownFiles_profile.zip
+
+[make_unknownFiles.js]
+skip-if = true # Only used for recreating unknownFiles_profile.zip
+[make_unsetLastAccessTime.js]
+skip-if = true # Only used for recreating unsetLastAccessTime_profile.zip
+[test_allowListFiles.js]
+[test_basics.js]
+[test_bad_origin_directory.js]
+[test_createLocalStorage.js]
+[test_clearStoragesForPrincipal.js]
+[test_clearStoragesForOriginAttributesPattern.js]
+[test_estimateOrigin.js]
+[test_getUsage.js]
+[test_groupMismatch.js]
+[test_initTemporaryStorage.js]
+[test_listOrigins.js]
+[test_originEndsWithDot.js]
+[test_originMismatch.js]
+[test_originWithCaret.js]
+[test_orpahnedQuotaObject.js]
+[test_persist.js]
+[test_persist_eviction.js]
+[test_persist_globalLimit.js]
+[test_persist_groupLimit.js]
+[test_removeLocalStorage.js]
+[test_simpledb.js]
+[test_specialOrigins.js]
+[test_storagePressure.js]
+skip-if = condprof
+[test_tempMetadataCleanup.js]
+[test_unaccessedOrigins.js]
+[test_unknownFiles.js]
+[test_unsetLastAccessTime.js]
+support-files =
+  unsetLastAccessTime_profile.zip
+[test_validOrigins.js]