6 files changed, 29 insertions, 43 deletions
diff --git a/dom/canvas/CanvasRenderingContext2D.cpp b/dom/canvas/CanvasRenderingContext2D.cpp
index 1a79a9f734..54711aa981 100644
--- a/dom/canvas/CanvasRenderingContext2D.cpp
+++ b/dom/canvas/CanvasRenderingContext2D.cpp
@@ -2216,14 +2216,16 @@ void CanvasRenderingContext2D::Transform(double aM11, double aM12, double aM21,
 
 already_AddRefed<DOMMatrix> CanvasRenderingContext2D::GetTransform(
     ErrorResult& aError) {
-  if (!EnsureTarget(aError)) {
+  // If we are silently failing, then we still need to return a transform while
+  // we are in the process of recovering.
+  Matrix transform;
+  if (EnsureTarget(aError)) {
+    transform = mTarget->GetTransform();
+  } else if (aError.Failed()) {
     return nullptr;
   }
 
-  MOZ_ASSERT(IsTargetValid());
-
-  RefPtr<DOMMatrix> matrix =
-      new DOMMatrix(GetParentObject(), mTarget->GetTransform());
+  RefPtr<DOMMatrix> matrix = new DOMMatrix(GetParentObject(), transform);
   return matrix.forget();
 }
 
diff --git a/dom/canvas/test/test_accelerated_canvas_context_loss.html b/dom/canvas/test/test_accelerated_canvas_context_loss.html
index 6172420bcb..610c8d8fc3 100644
--- a/dom/canvas/test/test_accelerated_canvas_context_loss.html
+++ b/dom/canvas/test/test_accelerated_canvas_context_loss.html
@@ -58,6 +58,12 @@ let countRestoredEvents = 0;
 
 function onContextLost() {
   ok(context.isContextLost(), "Canvas context should be lost during contextlost event");
+
+  try {
+    let transform = context.getTransform();
+    ok(transform.isIdentity, "Canvas context should return identity transform while context lost");
+  } catch (e) {}
+
   countLostEvents += 1;
 }
 
@@ -88,6 +94,12 @@ async function start() {
 
     ok(!context.isContextLost(), "Canvas context should not be lost after initial fill");
 
+    let transform = context.getTransform();
+    ok(transform.isIdentity, "Canvas context should default to identity transform");
+    context.setTransform(2.0, 3.0, 4.0, 5.0, 6.0, 7.0);
+    transform = context.getTransform();
+    ok(!transform.isIdentity, "Canvas context should have non-identity transform");
+
     const restarted = await restartGPUProcess();
     const expectedEvents = restarted ? 1 : 0;
 
diff --git a/dom/indexedDB/IDBFactory.cpp b/dom/indexedDB/IDBFactory.cpp
index 51d4c4df23..c0dc5aeab2 100644
--- a/dom/indexedDB/IDBFactory.cpp
+++ b/dom/indexedDB/IDBFactory.cpp
@@ -470,7 +470,13 @@ RefPtr<IDBOpenDBRequest> IDBFactory::DeleteDatabase(
                       /* aDeleting */ true, aCallerType, aRv);
 }
 
-already_AddRefed<Promise> IDBFactory::Databases(JSContext* const aCx) {
+already_AddRefed<Promise> IDBFactory::Databases(JSContext* const aCx,
+                                                ErrorResult& aRv) {
+  if (NS_WARN_IF(!GetOwnerGlobal())) {
+    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR);
+    return nullptr;
+  }
+
   RefPtr<Promise> promise = Promise::CreateInfallible(GetOwnerGlobal());
 
   // Nothing can be done here if we have previously failed to create a
diff --git a/dom/indexedDB/IDBFactory.h b/dom/indexedDB/IDBFactory.h
index 7139b26f9c..d64d571a05 100644
--- a/dom/indexedDB/IDBFactory.h
+++ b/dom/indexedDB/IDBFactory.h
@@ -162,7 +162,7 @@ class IDBFactory final : public GlobalTeardownObserver, public nsWrapperCache {
       JSContext* aCx, const nsAString& aName, const IDBOpenDBOptions& aOptions,
       CallerType aCallerType, ErrorResult& aRv);
 
-  already_AddRefed<Promise> Databases(JSContext* aCx);
+  already_AddRefed<Promise> Databases(JSContext* aCx, ErrorResult& aRv);
 
   int16_t Cmp(JSContext* aCx, JS::Handle<JS::Value> aFirst,
               JS::Handle<JS::Value> aSecond, ErrorResult& aRv);
diff --git a/dom/media/platforms/wmf/DXVA2Manager.cpp b/dom/media/platforms/wmf/DXVA2Manager.cpp
index 9efe9dab55..064efd8209 100644
--- a/dom/media/platforms/wmf/DXVA2Manager.cpp
+++ b/dom/media/platforms/wmf/DXVA2Manager.cpp
@@ -127,35 +127,6 @@ using namespace gfx;
 StaticRefPtr<ID3D11Device> sDevice;
 StaticMutex sDeviceMutex;
 
-// We found an issue where the ID3D11VideoDecoder won't release its underlying
-// resources properly if the decoder iscreated from a compositor device by
-// ourselves. This problem has been observed with both VP9 and, reportedly, AV1
-// decoders, it does not seem to affect the H264 decoder, but the underlying
-// decoder created by MFT seems not having this issue.
-// Therefore, when checking whether we can use hardware decoding, we should use
-// a non-compositor device to create a decoder in order to prevent resource
-// leaking that can significantly degrade the performance. For the actual
-// decoding, we will still use the compositor device if it's avaiable in order
-// to avoid video copying.
-static ID3D11Device* GetDeviceForDecoderCheck() {
-  StaticMutexAutoLock lock(sDeviceMutex);
-  if (AppShutdown::IsInOrBeyond(ShutdownPhase::XPCOMShutdown)) {
-    return nullptr;
-  }
-  if (!sDevice) {
-    sDevice = gfx::DeviceManagerDx::Get()->CreateDecoderDevice(
-        {DeviceManagerDx::DeviceFlag::disableDeviceReuse});
-    auto clearOnShutdown = [] { ClearOnShutdown(&sDevice); };
-    if (!NS_IsMainThread()) {
-      Unused << NS_DispatchToMainThread(
-          NS_NewRunnableFunction(__func__, clearOnShutdown));
-    } else {
-      clearOnShutdown();
-    }
-  }
-  return sDevice.get();
-}
-
 void GetDXVA2ExtendedFormatFromMFMediaType(IMFMediaType* pType,
                                            DXVA2_ExtendedFormat* pFormat) {
   // Get the interlace mode.
@@ -1190,14 +1161,8 @@ D3D11DXVA2Manager::ConfigureForSize(IMFMediaType* aInputType,
 
 bool D3D11DXVA2Manager::CanCreateDecoder(
     const D3D11_VIDEO_DECODER_DESC& aDesc) const {
-  RefPtr<ID3D11Device> device = GetDeviceForDecoderCheck();
-  if (!device) {
-    LOG("Can't create decoder due to lacking of ID3D11Device!");
-    return false;
-  }
-
   RefPtr<ID3D11VideoDevice> videoDevice;
-  HRESULT hr = device->QueryInterface(
+  HRESULT hr = mDevice->QueryInterface(
       static_cast<ID3D11VideoDevice**>(getter_AddRefs(videoDevice)));
   if (FAILED(hr)) {
     LOG("Failed to query ID3D11VideoDevice!");
diff --git a/dom/webidl/IDBFactory.webidl b/dom/webidl/IDBFactory.webidl
index 76553037fc..9e9153324f 100644
--- a/dom/webidl/IDBFactory.webidl
+++ b/dom/webidl/IDBFactory.webidl
@@ -39,6 +39,7 @@ interface IDBFactory {
   deleteDatabase(DOMString name,
                  optional IDBOpenDBOptions options = {});
 
+  [Throws]
   Promise<sequence<IDBDatabaseInfo>> databases();
 
   [Throws]