Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 1122 insertions, 0 deletions

diff --git a/toolkit/components/startup/nsAppStartup.cpp b/toolkit/components/startup/nsAppStartup.cpp
new file mode 100644
index 0000000000..3314cb813f
--- /dev/null
+++ b/toolkit/components/startup/nsAppStartup.cpp
@@ -0,0 +1,1122 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 "nsAppStartup.h"
+
+#include "nsComponentManagerUtils.h"
+#include "nsIAppShellService.h"
+#include "nsPIDOMWindow.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIFile.h"
+#include "nsIObserverService.h"
+#include "nsIPrefBranch.h"
+#include "nsIPrefService.h"
+#include "nsIProcess.h"
+#include "nsIToolkitProfile.h"
+#include "nsIWebBrowserChrome.h"
+#include "nsIWindowMediator.h"
+#include "nsIXULRuntime.h"
+#include "nsIAppWindow.h"
+#include "nsNativeCharsetUtils.h"
+#include "nsThreadUtils.h"
+#include "nsString.h"
+#include "mozilla/AppShutdown.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/Try.h"
+#include "mozilla/Unused.h"
+
+#include "GeckoProfiler.h"
+#include "prprf.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsWidgetsCID.h"
+#include "nsAppRunner.h"
+#include "nsAppShellCID.h"
+#include "nsXPCOMCIDInternal.h"
+#include "mozilla/Services.h"
+#include "jsapi.h"
+#include "js/Date.h"
+#include "js/PropertyAndElement.h"  // JS_DefineProperty
+#include "prenv.h"
+#include "nsAppDirectoryServiceDefs.h"
+
+#if defined(XP_WIN)
+// Prevent collisions with nsAppStartup::GetStartupInfo()
+#  undef GetStartupInfo
+
+#  include <windows.h>
+#elif defined(XP_DARWIN)
+#  include <mach/mach_time.h>
+#endif
+
+#include "mozilla/IOInterposer.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/StartupTimeline.h"
+
+static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
+
+#define kPrefLastSuccess "toolkit.startup.last_success"
+#define kPrefMaxResumedCrashes "toolkit.startup.max_resumed_crashes"
+#define kPrefRecentCrashes "toolkit.startup.recent_crashes"
+#define kPrefAlwaysUseSafeMode "toolkit.startup.always_use_safe_mode"
+
+#define kNanosecondsPerSecond 1000000000.0
+
+#if defined(XP_WIN)
+#  include "mozilla/PreXULSkeletonUI.h"
+
+#  include "mozilla/perfprobe.h"
+/**
+ * Events sent to the system for profiling purposes
+ */
+// Keep them syncronized with the .mof file
+
+// Process-wide GUID, used by the OS to differentiate sources
+// {509962E0-406B-46F4-99BA-5A009F8D2225}
+// Keep it synchronized with the .mof file
+#  define NS_APPLICATION_TRACING_CID                   \
+    {                                                  \
+      0x509962E0, 0x406B, 0x46F4, {                    \
+        0x99, 0xBA, 0x5A, 0x00, 0x9F, 0x8D, 0x22, 0x25 \
+      }                                                \
+    }
+
+// Event-specific GUIDs, used by the OS to differentiate events
+// {A3DA04E0-57D7-482A-A1C1-61DA5F95BACB}
+#  define NS_PLACES_INIT_COMPLETE_EVENT_CID            \
+    {                                                  \
+      0xA3DA04E0, 0x57D7, 0x482A, {                    \
+        0xA1, 0xC1, 0x61, 0xDA, 0x5F, 0x95, 0xBA, 0xCB \
+      }                                                \
+    }
+// {917B96B1-ECAD-4DAB-A760-8D49027748AE}
+#  define NS_SESSION_STORE_WINDOW_RESTORED_EVENT_CID   \
+    {                                                  \
+      0x917B96B1, 0xECAD, 0x4DAB, {                    \
+        0xA7, 0x60, 0x8D, 0x49, 0x02, 0x77, 0x48, 0xAE \
+      }                                                \
+    }
+// {26D1E091-0AE7-4F49-A554-4214445C505C}
+#  define NS_XPCOM_SHUTDOWN_EVENT_CID                  \
+    {                                                  \
+      0x26D1E091, 0x0AE7, 0x4F49, {                    \
+        0xA5, 0x54, 0x42, 0x14, 0x44, 0x5C, 0x50, 0x5C \
+      }                                                \
+    }
+
+static NS_DEFINE_CID(kApplicationTracingCID, NS_APPLICATION_TRACING_CID);
+static NS_DEFINE_CID(kPlacesInitCompleteCID, NS_PLACES_INIT_COMPLETE_EVENT_CID);
+static NS_DEFINE_CID(kSessionStoreWindowRestoredCID,
+                     NS_SESSION_STORE_WINDOW_RESTORED_EVENT_CID);
+static NS_DEFINE_CID(kXPCOMShutdownCID, NS_XPCOM_SHUTDOWN_EVENT_CID);
+#endif  // defined(XP_WIN)
+
+using namespace mozilla;
+
+class nsAppExitEvent : public mozilla::Runnable {
+ private:
+  RefPtr<nsAppStartup> mService;
+
+ public:
+  explicit nsAppExitEvent(nsAppStartup* service)
+      : mozilla::Runnable("nsAppExitEvent"), mService(service) {}
+
+  NS_IMETHOD Run() override {
+    // Tell the appshell to exit
+    mService->mAppShell->Exit();
+
+    mService->mRunning = false;
+    return NS_OK;
+  }
+};
+
+/**
+ * Computes an approximation of the absolute time represented by @a stamp
+ * which is comparable to those obtained via PR_Now(). If the current absolute
+ * time varies a lot (e.g. DST adjustments) since the first call then the
+ * resulting times may be inconsistent.
+ *
+ * @param stamp The timestamp to be converted
+ * @returns The converted timestamp
+ */
+static uint64_t ComputeAbsoluteTimestamp(TimeStamp stamp) {
+  static PRTime sAbsoluteNow = PR_Now();
+  static TimeStamp sMonotonicNow = TimeStamp::Now();
+
+  return sAbsoluteNow - (sMonotonicNow - stamp).ToMicroseconds();
+}
+
+//
+// nsAppStartup
+//
+
+nsAppStartup::nsAppStartup()
+    : mConsiderQuitStopper(0),
+      mRunning(false),
+      mShuttingDown(false),
+      mStartingUp(true),
+      mAttemptingQuit(false),
+      mInterrupted(false),
+      mIsSafeModeNecessary(false),
+      mStartupCrashTrackingEnded(false) {
+  char* mozAppSilentStart = PR_GetEnv("MOZ_APP_SILENT_START");
+
+  /* When calling PR_SetEnv() with an empty value the existing variable may
+   * be unset or set to the empty string depending on the underlying platform
+   * thus we have to check if the variable is present and not empty. */
+  mWasSilentlyStarted =
+      mozAppSilentStart && (strcmp(mozAppSilentStart, "") != 0);
+
+  // Make sure to clear this in case we restart again non-silently.
+  PR_SetEnv("MOZ_APP_SILENT_START=");
+
+#ifdef XP_WIN
+  char* mozAppAllowWindowless = PR_GetEnv("MOZ_APP_ALLOW_WINDOWLESS");
+  mAllowWindowless =
+      mozAppAllowWindowless && (strcmp(mozAppAllowWindowless, "") != 0);
+#endif
+}
+
+nsresult nsAppStartup::Init() {
+  nsresult rv;
+
+  // Create widget application shell
+  mAppShell = do_GetService(kAppShellCID, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+  if (!os) return NS_ERROR_FAILURE;
+
+  os->AddObserver(this, "quit-application", true);
+  os->AddObserver(this, "quit-application-forced", true);
+  os->AddObserver(this, "sessionstore-init-started", true);
+  os->AddObserver(this, "sessionstore-windows-restored", true);
+  os->AddObserver(this, "profile-change-teardown", true);
+  os->AddObserver(this, "xul-window-registered", true);
+  os->AddObserver(this, "xul-window-destroyed", true);
+  os->AddObserver(this, "profile-before-change", true);
+  os->AddObserver(this, "xpcom-shutdown", true);
+
+#if defined(XP_WIN)
+  os->AddObserver(this, "places-init-complete", true);
+  // This last event is only interesting to us for xperf-based measures
+
+  // Initialize interaction with profiler
+  mProbesManager =
+      new ProbeManager(kApplicationTracingCID, "Application startup probe"_ns);
+  // Note: The operation is meant mostly for in-house profiling.
+  // Therefore, we do not warn if probes manager cannot be initialized
+
+  if (mProbesManager) {
+    mPlacesInitCompleteProbe = mProbesManager->GetProbe(
+        kPlacesInitCompleteCID, "places-init-complete"_ns);
+    NS_WARNING_ASSERTION(mPlacesInitCompleteProbe,
+                         "Cannot initialize probe 'places-init-complete'");
+
+    mSessionWindowRestoredProbe = mProbesManager->GetProbe(
+        kSessionStoreWindowRestoredCID, "sessionstore-windows-restored"_ns);
+    NS_WARNING_ASSERTION(
+        mSessionWindowRestoredProbe,
+        "Cannot initialize probe 'sessionstore-windows-restored'");
+
+    mXPCOMShutdownProbe =
+        mProbesManager->GetProbe(kXPCOMShutdownCID, "xpcom-shutdown"_ns);
+    NS_WARNING_ASSERTION(mXPCOMShutdownProbe,
+                         "Cannot initialize probe 'xpcom-shutdown'");
+
+    rv = mProbesManager->StartSession();
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                         "Cannot initialize system probe manager");
+  }
+#endif  // defined(XP_WIN)
+
+  return NS_OK;
+}
+
+//
+// nsAppStartup->nsISupports
+//
+
+NS_IMPL_ISUPPORTS(nsAppStartup, nsIAppStartup, nsIWindowCreator, nsIObserver,
+                  nsISupportsWeakReference)
+
+//
+// nsAppStartup->nsIAppStartup
+//
+
+NS_IMETHODIMP
+nsAppStartup::CreateHiddenWindow() {
+#if defined(MOZ_WIDGET_UIKIT)
+  return NS_OK;
+#else
+  nsCOMPtr<nsIAppShellService> appShellService(
+      do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  NS_ENSURE_TRUE(appShellService, NS_ERROR_FAILURE);
+
+  return appShellService->CreateHiddenWindow();
+#endif
+}
+
+NS_IMETHODIMP
+nsAppStartup::DestroyHiddenWindow() {
+#if defined(MOZ_WIDGET_UIKIT)
+  return NS_OK;
+#else
+  nsCOMPtr<nsIAppShellService> appShellService(
+      do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  NS_ENSURE_TRUE(appShellService, NS_ERROR_FAILURE);
+
+  return appShellService->DestroyHiddenWindow();
+#endif
+}
+
+NS_IMETHODIMP
+nsAppStartup::Run(void) {
+  NS_ASSERTION(!mRunning, "Reentrant appstartup->Run()");
+
+  // If we have no windows open and no explicit calls to
+  // enterLastWindowClosingSurvivalArea, or somebody has explicitly called
+  // quit, don't bother running the event loop which would probably leave us
+  // with a zombie process.
+
+  if (!mShuttingDown && mConsiderQuitStopper != 0) {
+#ifdef XP_MACOSX
+    EnterLastWindowClosingSurvivalArea();
+#elif defined(XP_WIN)
+    if (mAllowWindowless) {
+      EnterLastWindowClosingSurvivalArea();
+    }
+#endif
+
+    mRunning = true;
+
+    nsresult rv = mAppShell->Run();
+    if (NS_FAILED(rv)) return rv;
+  }
+
+  // Make sure that the appropriate quit notifications have been dispatched
+  // regardless of whether the event loop has spun or not. Note that this call
+  // is a no-op if Quit has already been called previously.
+  bool userAllowedQuit = true;
+  Quit(eForceQuit, 0, &userAllowedQuit);
+
+  nsresult retval = NS_OK;
+  if (mozilla::AppShutdown::IsRestarting()) {
+    retval = NS_SUCCESS_RESTART_APP;
+  }
+
+  return retval;
+}
+
+NS_IMETHODIMP
+nsAppStartup::Quit(uint32_t aMode, int aExitCode, bool* aUserAllowedQuit) {
+  if ((aMode & eSilently) != 0 && (aMode & eRestart) == 0) {
+    // eSilently is only valid when combined with eRestart.
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  uint32_t ferocity = (aMode & 0xF);
+
+  // If the shutdown was cancelled due to a hidden window or
+  // because one of the windows was not permitted to be closed,
+  // return NS_OK with |aUserAllowedQuit| = false.
+  *aUserAllowedQuit = false;
+
+  // Quit the application. We will asynchronously call the appshell's
+  // Exit() method via nsAppExitEvent to allow one last pass
+  // through any events in the queue. This guarantees a tidy cleanup.
+  nsresult rv = NS_OK;
+  bool postedExitEvent = false;
+
+  if (mShuttingDown) return NS_OK;
+
+  // If we're considering quitting, we will only do so if:
+  if (ferocity == eConsiderQuit) {
+#ifdef XP_MACOSX
+    nsCOMPtr<nsIAppShellService> appShell(
+        do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+    int32_t suspiciousCount = 1;
+#endif
+
+    if (mConsiderQuitStopper == 0) {
+      // there are no windows...
+      ferocity = eAttemptQuit;
+    }
+#ifdef XP_MACOSX
+    else if (mConsiderQuitStopper == suspiciousCount) {
+      // ... or there is only a hiddenWindow left, and it's useless:
+
+      // Failure shouldn't be fatal, but will abort quit attempt:
+      if (!appShell) return NS_OK;
+
+      bool usefulHiddenWindow;
+      appShell->GetApplicationProvidedHiddenWindow(&usefulHiddenWindow);
+      nsCOMPtr<nsIAppWindow> hiddenWindow;
+      appShell->GetHiddenWindow(getter_AddRefs(hiddenWindow));
+      // If the remaining windows are useful, we won't quit:
+      if (!hiddenWindow || usefulHiddenWindow) {
+        return NS_OK;
+      }
+
+      ferocity = eAttemptQuit;
+    }
+#endif
+  }
+
+  nsCOMPtr<nsIObserverService> obsService;
+  if (ferocity == eAttemptQuit || ferocity == eForceQuit) {
+    nsCOMPtr<nsISimpleEnumerator> windowEnumerator;
+    nsCOMPtr<nsIWindowMediator> mediator(
+        do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+    if (mediator) {
+      mediator->GetEnumerator(nullptr, getter_AddRefs(windowEnumerator));
+      if (windowEnumerator) {
+        bool more;
+        windowEnumerator->HasMoreElements(&more);
+        // If we reported no windows, we definitely shouldn't be
+        // iterating any here.
+        MOZ_ASSERT_IF(!mConsiderQuitStopper, !more);
+
+        while (more) {
+          nsCOMPtr<nsISupports> window;
+          windowEnumerator->GetNext(getter_AddRefs(window));
+          nsCOMPtr<nsPIDOMWindowOuter> domWindow(do_QueryInterface(window));
+          if (domWindow) {
+            if (!domWindow->CanClose()) {
+              return NS_OK;
+            }
+          }
+          windowEnumerator->HasMoreElements(&more);
+        }
+      }
+    }
+
+    PROFILER_MARKER_UNTYPED("Shutdown start", OTHER);
+    mozilla::RecordShutdownStartTimeStamp();
+
+    *aUserAllowedQuit = true;
+    mShuttingDown = true;
+    auto shutdownMode = ((aMode & eRestart) != 0)
+                            ? mozilla::AppShutdownMode::Restart
+                            : mozilla::AppShutdownMode::Normal;
+    // TODO: Add (or pass in) more reasons here for Mac and Linux, see
+    // bug 1827643 and bug 1827644.
+    // See as example the Windows WM_ENDSESSION handling.
+    auto shutdownReason = ((aMode & eRestart) != 0)
+                              ? mozilla::AppShutdownReason::AppRestart
+                              : mozilla::AppShutdownReason::AppClose;
+    mozilla::AppShutdown::Init(shutdownMode, aExitCode, shutdownReason);
+
+    if (mozilla::AppShutdown::IsRestarting()) {
+      // Mark the next startup as a restart.
+      PR_SetEnv("MOZ_APP_RESTART=1");
+
+      /* Firefox-restarts reuse the process so regular process start-time isn't
+         a useful indicator of startup time anymore. */
+      TimeStamp::RecordProcessRestart();
+    }
+
+    if ((aMode & eSilently) != 0) {
+      // Mark the next startup as a silent restart.
+      // See the eSilently definition for details.
+      PR_SetEnv("MOZ_APP_SILENT_START=1");
+    }
+
+    obsService = mozilla::services::GetObserverService();
+
+    if (!mAttemptingQuit) {
+      mAttemptingQuit = true;
+#ifdef XP_MACOSX
+      // now even the Mac wants to quit when the last window is closed
+      ExitLastWindowClosingSurvivalArea();
+#elif defined(XP_WIN)
+      if (mAllowWindowless) {
+        ExitLastWindowClosingSurvivalArea();
+      }
+#endif
+      if (obsService)
+        obsService->NotifyObservers(nullptr, "quit-application-granted",
+                                    nullptr);
+    }
+
+    /* Enumerate through each open window and close it. It's important to do
+       this before we forcequit because this can control whether we really quit
+       at all. e.g. if one of these windows has an unload handler that
+       opens a new window. Ugh. I know. */
+    CloseAllWindows();
+
+    if (mediator) {
+      if (ferocity == eAttemptQuit) {
+        ferocity = eForceQuit;  // assume success
+
+        /* Were we able to immediately close all windows? if not, eAttemptQuit
+           failed. This could happen for a variety of reasons; in fact it's
+           very likely. Perhaps we're being called from JS and the window->Close
+           method hasn't had a chance to wrap itself up yet. So give up.
+           We'll return (with eConsiderQuit) as the remaining windows are
+           closed. */
+        mediator->GetEnumerator(nullptr, getter_AddRefs(windowEnumerator));
+        if (windowEnumerator) {
+          bool more;
+          while (NS_SUCCEEDED(windowEnumerator->HasMoreElements(&more)) &&
+                 more) {
+            /* we can't quit immediately. we'll try again as the last window
+               finally closes. */
+            ferocity = eAttemptQuit;
+            nsCOMPtr<nsISupports> window;
+            windowEnumerator->GetNext(getter_AddRefs(window));
+            nsCOMPtr<nsPIDOMWindowOuter> domWindow = do_QueryInterface(window);
+            if (domWindow) {
+              if (!domWindow->Closed()) {
+                rv = NS_ERROR_FAILURE;
+                break;
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+
+  if (ferocity == eForceQuit) {
+    // do it!
+    mozilla::AppShutdown::OnShutdownConfirmed();
+
+    // No chance of the shutdown being cancelled from here on; tell people
+    // we're shutting down for sure while all services are still available.
+    bool isRestarting = mozilla::AppShutdown::IsRestarting();
+    mozilla::AppShutdown::AdvanceShutdownPhase(
+        mozilla::ShutdownPhase::AppShutdownConfirmed,
+        isRestarting ? u"restart" : u"shutdown");
+
+    if (!mRunning) {
+      postedExitEvent = true;
+    } else {
+      // no matter what, make sure we send the exit event.  If
+      // worst comes to worst, we'll do a leaky shutdown but we WILL
+      // shut down. Well, assuming that all *this* stuff works ;-).
+      nsCOMPtr<nsIRunnable> event = new nsAppExitEvent(this);
+      rv = NS_DispatchToCurrentThread(event);
+      if (NS_SUCCEEDED(rv)) {
+        postedExitEvent = true;
+      } else {
+        NS_WARNING("failed to dispatch nsAppExitEvent");
+      }
+    }
+  }
+
+  // turn off the reentrancy check flag, but not if we have
+  // more asynchronous work to do still.
+  if (!postedExitEvent) {
+    mShuttingDown = false;
+  }
+  return rv;
+}
+
+// Ensure ShutdownPhase.h and nsIAppStartup.idl are in sync.
+static_assert(int(nsIAppStartup::SHUTDOWN_PHASE_NOTINSHUTDOWN) ==
+                      int(mozilla::ShutdownPhase::NotInShutdown) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWNCONFIRMED) ==
+                      int(mozilla::ShutdownPhase::AppShutdownConfirmed) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWNNETTEARDOWN) ==
+                      int(mozilla::ShutdownPhase::AppShutdownNetTeardown) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWNTEARDOWN) ==
+                      int(mozilla::ShutdownPhase::AppShutdownTeardown) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWN) ==
+                      int(mozilla::ShutdownPhase::AppShutdown) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWNQM) ==
+                      int(mozilla::ShutdownPhase::AppShutdownQM) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_APPSHUTDOWNRELEMETRY) ==
+                      int(mozilla::ShutdownPhase::AppShutdownTelemetry) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_XPCOMWILLSHUTDOWN) ==
+                      int(mozilla::ShutdownPhase::XPCOMWillShutdown) &&
+                  int(nsIAppStartup::SHUTDOWN_PHASE_XPCOMSHUTDOWN) ==
+                      int(mozilla::ShutdownPhase::XPCOMShutdown),
+              "IDLShutdownPhase values are as expected");
+
+// Helper for safe conversion to native shutdown phases.
+Result<ShutdownPhase, nsresult> IDLShutdownPhaseToNative(
+    nsAppStartup::IDLShutdownPhase aPhase) {
+  if (uint8_t(aPhase) <= nsIAppStartup::SHUTDOWN_PHASE_XPCOMSHUTDOWN) {
+    return ShutdownPhase(aPhase);
+  }
+  return Err(NS_ERROR_ILLEGAL_VALUE);
+}
+
+NS_IMETHODIMP
+nsAppStartup::AdvanceShutdownPhase(IDLShutdownPhase aPhase) {
+  ShutdownPhase nativePhase;
+  MOZ_TRY_VAR(nativePhase, IDLShutdownPhaseToNative(aPhase));
+  AppShutdown::AdvanceShutdownPhase(nativePhase);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::IsInOrBeyondShutdownPhase(IDLShutdownPhase aPhase,
+                                        bool* aIsInOrBeyond) {
+  ShutdownPhase nativePhase;
+  MOZ_TRY_VAR(nativePhase, IDLShutdownPhaseToNative(aPhase));
+  *aIsInOrBeyond = AppShutdown::IsInOrBeyond(nativePhase);
+  return NS_OK;
+}
+
+void nsAppStartup::CloseAllWindows() {
+  nsCOMPtr<nsIWindowMediator> mediator(
+      do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+
+  nsCOMPtr<nsISimpleEnumerator> windowEnumerator;
+
+  mediator->GetEnumerator(nullptr, getter_AddRefs(windowEnumerator));
+
+  if (!windowEnumerator) return;
+
+  bool more;
+  while (NS_SUCCEEDED(windowEnumerator->HasMoreElements(&more)) && more) {
+    nsCOMPtr<nsISupports> isupports;
+    if (NS_FAILED(windowEnumerator->GetNext(getter_AddRefs(isupports)))) break;
+
+    nsCOMPtr<nsPIDOMWindowOuter> window = do_QueryInterface(isupports);
+    NS_ASSERTION(window, "not an nsPIDOMWindow");
+    if (window) {
+      window->ForceClose();
+    }
+  }
+}
+
+NS_IMETHODIMP
+nsAppStartup::EnterLastWindowClosingSurvivalArea(void) {
+  ++mConsiderQuitStopper;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::ExitLastWindowClosingSurvivalArea(void) {
+  NS_ASSERTION(mConsiderQuitStopper > 0, "consider quit stopper out of bounds");
+  --mConsiderQuitStopper;
+
+  if (mRunning) {
+    bool userAllowedQuit = false;
+
+    // A previous call to Quit may have told all windows to close and then
+    // bailed out waiting for that to happen. This is how we get back into Quit
+    // after each window closes so the exit process can continue when ready.
+    // Make sure to pass along the exit code that was initially passed to Quit.
+    Quit(eConsiderQuit, mozilla::AppShutdown::GetExitCode(), &userAllowedQuit);
+  }
+
+  return NS_OK;
+}
+
+//
+// nsAppStartup->nsIAppStartup2
+//
+
+NS_IMETHODIMP
+nsAppStartup::GetShuttingDown(bool* aResult) {
+  *aResult = AppShutdown::IsInOrBeyond(ShutdownPhase::AppShutdownConfirmed);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetStartingUp(bool* aResult) {
+  *aResult = mStartingUp;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::DoneStartingUp() {
+  // This must be called once at most
+  MOZ_ASSERT(mStartingUp);
+
+  mStartingUp = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetRestarting(bool* aResult) {
+  *aResult = mozilla::AppShutdown::IsRestarting();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetWasRestarted(bool* aResult) {
+  char* mozAppRestart = PR_GetEnv("MOZ_APP_RESTART");
+
+  /* When calling PR_SetEnv() with an empty value the existing variable may
+   * be unset or set to the empty string depending on the underlying platform
+   * thus we have to check if the variable is present and not empty. */
+  *aResult = mozAppRestart && (strcmp(mozAppRestart, "") != 0);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetWasSilentlyStarted(bool* aResult) {
+  *aResult = mWasSilentlyStarted;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetSecondsSinceLastOSRestart(int64_t* aResult) {
+#if defined(XP_WIN)
+  *aResult = int64_t(GetTickCount64() / 1000ull);
+  return NS_OK;
+#elif defined(XP_DARWIN)
+  uint64_t absTime = mach_absolute_time();
+  mach_timebase_info_data_t timebaseInfo;
+  mach_timebase_info(&timebaseInfo);
+  double toNanoseconds =
+      double(timebaseInfo.numer) / double(timebaseInfo.denom);
+  *aResult =
+      std::llround(double(absTime) * toNanoseconds / kNanosecondsPerSecond);
+  return NS_OK;
+#else
+  return NS_ERROR_NOT_IMPLEMENTED;
+#endif
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetShowedPreXULSkeletonUI(bool* aResult) {
+#if defined(XP_WIN)
+  *aResult = GetPreXULSkeletonUIWasShown();
+#else
+  *aResult = false;
+#endif
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::SetInterrupted(bool aInterrupted) {
+  mInterrupted = aInterrupted;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetInterrupted(bool* aInterrupted) {
+  *aInterrupted = mInterrupted;
+  return NS_OK;
+}
+
+//
+// nsAppStartup->nsIWindowCreator
+//
+
+NS_IMETHODIMP
+nsAppStartup::CreateChromeWindow(nsIWebBrowserChrome* aParent,
+                                 uint32_t aChromeFlags,
+                                 nsIOpenWindowInfo* aOpenWindowInfo,
+                                 bool* aCancel, nsIWebBrowserChrome** _retval) {
+  NS_ENSURE_ARG_POINTER(aCancel);
+  NS_ENSURE_ARG_POINTER(_retval);
+  *aCancel = false;
+  *_retval = 0;
+
+  // Non-modal windows cannot be opened if we are attempting to quit
+  if (mAttemptingQuit &&
+      (aChromeFlags & nsIWebBrowserChrome::CHROME_MODAL) == 0)
+    return NS_ERROR_ILLEGAL_DURING_SHUTDOWN;
+
+  // Fission windows must also be marked as remote
+  if ((aChromeFlags & nsIWebBrowserChrome::CHROME_FISSION_WINDOW) &&
+      !(aChromeFlags & nsIWebBrowserChrome::CHROME_REMOTE_WINDOW)) {
+    NS_WARNING("Cannot create non-remote fission window!");
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIAppWindow> newWindow;
+
+  if (aParent) {
+    nsCOMPtr<nsIAppWindow> appParent(do_GetInterface(aParent));
+    NS_ASSERTION(appParent,
+                 "window created using non-app parent. that's unexpected, but "
+                 "may work.");
+
+    if (appParent)
+      appParent->CreateNewWindow(aChromeFlags, aOpenWindowInfo,
+                                 getter_AddRefs(newWindow));
+    // And if it fails, don't try again without a parent. It could fail
+    // intentionally (bug 115969).
+  } else {  // try using basic methods:
+    MOZ_RELEASE_ASSERT(!aOpenWindowInfo,
+                       "Unexpected aOpenWindowInfo, we shouldn't ever have an "
+                       "nsIOpenWindowInfo without a parent");
+
+    /* You really shouldn't be making dependent windows without a parent.
+      But unparented modal (and therefore dependent) windows happen
+      in our codebase, so we allow it after some bellyaching: */
+    if (aChromeFlags & nsIWebBrowserChrome::CHROME_DEPENDENT)
+      NS_WARNING("dependent window created without a parent");
+
+    nsCOMPtr<nsIAppShellService> appShell(
+        do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+    if (!appShell) return NS_ERROR_FAILURE;
+
+    appShell->CreateTopLevelWindow(
+        0, 0, aChromeFlags, nsIAppShellService::SIZE_TO_CONTENT,
+        nsIAppShellService::SIZE_TO_CONTENT, getter_AddRefs(newWindow));
+  }
+
+  // if anybody gave us anything to work with, use it
+  if (newWindow) {
+    nsCOMPtr<nsIInterfaceRequestor> thing(do_QueryInterface(newWindow));
+    if (thing) CallGetInterface(thing.get(), _retval);
+  }
+
+  return *_retval ? NS_OK : NS_ERROR_FAILURE;
+}
+
+//
+// nsAppStartup->nsIObserver
+//
+
+NS_IMETHODIMP
+nsAppStartup::Observe(nsISupports* aSubject, const char* aTopic,
+                      const char16_t* aData) {
+  NS_ASSERTION(mAppShell, "appshell service notified before appshell built");
+  if (!strcmp(aTopic, "quit-application-forced")) {
+    mShuttingDown = true;
+  } else if (!strcmp(aTopic, "profile-change-teardown")) {
+    if (!mShuttingDown) {
+      EnterLastWindowClosingSurvivalArea();
+      CloseAllWindows();
+      ExitLastWindowClosingSurvivalArea();
+    }
+  } else if (!strcmp(aTopic, "xul-window-registered")) {
+    EnterLastWindowClosingSurvivalArea();
+  } else if (!strcmp(aTopic, "xul-window-destroyed")) {
+    ExitLastWindowClosingSurvivalArea();
+  } else if (!strcmp(aTopic, "sessionstore-windows-restored")) {
+    StartupTimeline::Record(StartupTimeline::SESSION_RESTORED);
+    IOInterposer::EnteringNextStage();
+#if defined(XP_WIN)
+    if (mSessionWindowRestoredProbe) {
+      mSessionWindowRestoredProbe->Trigger();
+    }
+  } else if (!strcmp(aTopic, "places-init-complete")) {
+    if (mPlacesInitCompleteProbe) {
+      mPlacesInitCompleteProbe->Trigger();
+    }
+#endif  // defined(XP_WIN)
+  } else if (!strcmp(aTopic, "sessionstore-init-started")) {
+    StartupTimeline::Record(StartupTimeline::SESSION_RESTORE_INIT);
+  } else if (!strcmp(aTopic, "xpcom-shutdown")) {
+    IOInterposer::EnteringNextStage();
+#if defined(XP_WIN)
+    if (mXPCOMShutdownProbe) {
+      mXPCOMShutdownProbe->Trigger();
+    }
+#endif  // defined(XP_WIN)
+  } else if (!strcmp(aTopic, "quit-application")) {
+    StartupTimeline::Record(StartupTimeline::QUIT_APPLICATION);
+  } else if (!strcmp(aTopic, "profile-before-change")) {
+    StartupTimeline::Record(StartupTimeline::PROFILE_BEFORE_CHANGE);
+  } else {
+    NS_ERROR("Unexpected observer topic.");
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetStartupInfo(JSContext* aCx,
+                             JS::MutableHandle<JS::Value> aRetval) {
+  JS::Rooted<JSObject*> obj(aCx, JS_NewPlainObject(aCx));
+
+  aRetval.setObject(*obj);
+
+  TimeStamp procTime = StartupTimeline::Get(StartupTimeline::PROCESS_CREATION);
+
+  if (procTime.IsNull()) {
+    procTime = TimeStamp::ProcessCreation();
+
+    StartupTimeline::Record(StartupTimeline::PROCESS_CREATION, procTime);
+  }
+
+  for (int i = StartupTimeline::PROCESS_CREATION;
+       i < StartupTimeline::MAX_EVENT_ID; ++i) {
+    StartupTimeline::Event ev = static_cast<StartupTimeline::Event>(i);
+    TimeStamp stamp = StartupTimeline::Get(ev);
+
+    if (stamp.IsNull() && (ev == StartupTimeline::MAIN)) {
+      // Always define main to aid with bug 689256.
+      stamp = procTime;
+      MOZ_ASSERT(!stamp.IsNull());
+    }
+
+    if (!stamp.IsNull()) {
+      if (stamp >= procTime) {
+        PRTime prStamp = ComputeAbsoluteTimestamp(stamp) / PR_USEC_PER_MSEC;
+        JS::Rooted<JSObject*> date(
+            aCx, JS::NewDateObject(aCx, JS::TimeClip(prStamp)));
+        JS_DefineProperty(aCx, obj, StartupTimeline::Describe(ev), date,
+                          JSPROP_ENUMERATE);
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::GetAutomaticSafeModeNecessary(bool* _retval) {
+  NS_ENSURE_ARG_POINTER(_retval);
+
+  bool alwaysSafe = false;
+  Preferences::GetBool(kPrefAlwaysUseSafeMode, &alwaysSafe);
+
+  if (!alwaysSafe) {
+#if DEBUG
+    mIsSafeModeNecessary = false;
+#else
+    mIsSafeModeNecessary &= !PR_GetEnv("MOZ_DISABLE_AUTO_SAFE_MODE");
+#endif
+  }
+
+  *_retval = mIsSafeModeNecessary;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::TrackStartupCrashBegin(bool* aIsSafeModeNecessary) {
+  const int32_t MAX_TIME_SINCE_STARTUP = 6 * 60 * 60 * 1000;
+  const int32_t MAX_STARTUP_BUFFER = 10;
+  nsresult rv;
+
+  mStartupCrashTrackingEnded = false;
+
+  StartupTimeline::Record(StartupTimeline::STARTUP_CRASH_DETECTION_BEGIN);
+
+  bool hasLastSuccess = Preferences::HasUserValue(kPrefLastSuccess);
+  if (!hasLastSuccess) {
+    // Clear so we don't get stuck with SafeModeNecessary returning true if we
+    // have had too many recent crashes and the last success pref is missing.
+    Preferences::ClearUser(kPrefRecentCrashes);
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  bool inSafeMode = false;
+  nsCOMPtr<nsIXULRuntime> xr = do_GetService(XULRUNTIME_SERVICE_CONTRACTID);
+  NS_ENSURE_TRUE(xr, NS_ERROR_FAILURE);
+
+  xr->GetInSafeMode(&inSafeMode);
+
+  PRTime replacedLockTime;
+  rv = xr->GetReplacedLockTime(&replacedLockTime);
+
+  if (NS_FAILED(rv) || !replacedLockTime) {
+    if (!inSafeMode) Preferences::ClearUser(kPrefRecentCrashes);
+    GetAutomaticSafeModeNecessary(aIsSafeModeNecessary);
+    return NS_OK;
+  }
+
+  // check whether safe mode is necessary
+  int32_t maxResumedCrashes = -1;
+  rv = Preferences::GetInt(kPrefMaxResumedCrashes, &maxResumedCrashes);
+  NS_ENSURE_SUCCESS(rv, NS_OK);
+
+  int32_t recentCrashes = 0;
+  Preferences::GetInt(kPrefRecentCrashes, &recentCrashes);
+  mIsSafeModeNecessary =
+      (recentCrashes > maxResumedCrashes && maxResumedCrashes != -1);
+
+  // Bug 731613 - Don't check if the last startup was a crash if
+  // XRE_PROFILE_PATH is set.  After profile manager, the profile lock's mod.
+  // time has been changed so can't be used on this startup. After a restart,
+  // it's safe to assume the last startup was successful.
+  char* xreProfilePath = PR_GetEnv("XRE_PROFILE_PATH");
+  if (xreProfilePath) {
+    GetAutomaticSafeModeNecessary(aIsSafeModeNecessary);
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  // time of last successful startup
+  int32_t lastSuccessfulStartup;
+  rv = Preferences::GetInt(kPrefLastSuccess, &lastSuccessfulStartup);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  int32_t lockSeconds = (int32_t)(replacedLockTime / PR_MSEC_PER_SEC);
+
+  // started close enough to good startup so call it good
+  if (lockSeconds <= lastSuccessfulStartup + MAX_STARTUP_BUFFER &&
+      lockSeconds >= lastSuccessfulStartup - MAX_STARTUP_BUFFER) {
+    GetAutomaticSafeModeNecessary(aIsSafeModeNecessary);
+    return NS_OK;
+  }
+
+  // sanity check that the pref set at last success is not greater than the
+  // current time
+  if (PR_Now() / PR_USEC_PER_SEC <= lastSuccessfulStartup)
+    return NS_ERROR_FAILURE;
+
+  // The last startup was a crash so include it in the count regardless of when
+  // it happened.
+  Telemetry::Accumulate(Telemetry::STARTUP_CRASH_DETECTED, true);
+
+  if (inSafeMode) {
+    GetAutomaticSafeModeNecessary(aIsSafeModeNecessary);
+    return NS_OK;
+  }
+
+  PRTime now = (PR_Now() / PR_USEC_PER_MSEC);
+  // if the last startup attempt which crashed was in the last 6 hours
+  if (replacedLockTime >= now - MAX_TIME_SINCE_STARTUP) {
+    NS_WARNING("Last startup was detected as a crash.");
+    recentCrashes++;
+    rv = Preferences::SetInt(kPrefRecentCrashes, recentCrashes);
+  } else {
+    // Otherwise ignore that crash and all previous since it may not be
+    // applicable anymore and we don't want someone to get stuck in safe mode if
+    // their prefs are read-only.
+    rv = Preferences::ClearUser(kPrefRecentCrashes);
+  }
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // recalculate since recent crashes count may have changed above
+  mIsSafeModeNecessary =
+      (recentCrashes > maxResumedCrashes && maxResumedCrashes != -1);
+
+  nsCOMPtr<nsIPrefService> prefs = Preferences::GetService();
+  rv = static_cast<Preferences*>(prefs.get())
+           ->SavePrefFileBlocking();  // flush prefs to disk since we are
+                                      // tracking crashes
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  GetAutomaticSafeModeNecessary(aIsSafeModeNecessary);
+  return rv;
+}
+
+static nsresult RemoveIncompleteStartupFile() {
+  nsCOMPtr<nsIFile> file;
+  MOZ_TRY(NS_GetSpecialDirectory(NS_APP_USER_PROFILE_LOCAL_50_DIR,
+                                 getter_AddRefs(file)));
+
+  return NS_DispatchBackgroundTask(NS_NewRunnableFunction(
+      "RemoveIncompleteStartupFile", [file = std::move(file)] {
+        auto incompleteStartup =
+            mozilla::startup::GetIncompleteStartupFile(file);
+        if (NS_WARN_IF(incompleteStartup.isErr())) {
+          return;
+        }
+        Unused << NS_WARN_IF(
+            NS_FAILED(incompleteStartup.unwrap()->Remove(false)));
+      }));
+}
+
+NS_IMETHODIMP
+nsAppStartup::TrackStartupCrashEnd() {
+  bool inSafeMode = false;
+  nsCOMPtr<nsIXULRuntime> xr = do_GetService(XULRUNTIME_SERVICE_CONTRACTID);
+  if (xr) xr->GetInSafeMode(&inSafeMode);
+
+  // return if we already ended or we're restarting into safe mode
+  if (mStartupCrashTrackingEnded || (mIsSafeModeNecessary && !inSafeMode))
+    return NS_OK;
+  mStartupCrashTrackingEnded = true;
+
+  StartupTimeline::Record(StartupTimeline::STARTUP_CRASH_DETECTION_END);
+
+  // Remove the incomplete startup canary file, so the next startup doesn't
+  // detect a recent startup crash.
+  Unused << NS_WARN_IF(NS_FAILED(RemoveIncompleteStartupFile()));
+
+  // Use the timestamp of XRE_main as an approximation for the lock file
+  // timestamp. See MAX_STARTUP_BUFFER for the buffer time period.
+  TimeStamp mainTime = StartupTimeline::Get(StartupTimeline::MAIN);
+  nsresult rv;
+
+  if (mainTime.IsNull()) {
+    NS_WARNING("Could not get StartupTimeline::MAIN time.");
+  } else {
+    uint64_t lockFileTime = ComputeAbsoluteTimestamp(mainTime);
+
+    rv = Preferences::SetInt(kPrefLastSuccess,
+                             (int32_t)(lockFileTime / PR_USEC_PER_SEC));
+
+    if (NS_FAILED(rv))
+      NS_WARNING("Could not set startup crash detection pref.");
+  }
+
+  if (inSafeMode && mIsSafeModeNecessary) {
+    // On a successful startup in automatic safe mode, allow the user one more
+    // crash in regular mode before returning to safe mode.
+    int32_t maxResumedCrashes = 0;
+    int32_t prefType;
+    rv = Preferences::GetRootBranch(PrefValueKind::Default)
+             ->GetPrefType(kPrefMaxResumedCrashes, &prefType);
+    NS_ENSURE_SUCCESS(rv, rv);
+    if (prefType == nsIPrefBranch::PREF_INT) {
+      rv = Preferences::GetInt(kPrefMaxResumedCrashes, &maxResumedCrashes);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+    rv = Preferences::SetInt(kPrefRecentCrashes, maxResumedCrashes);
+    NS_ENSURE_SUCCESS(rv, rv);
+  } else if (!inSafeMode) {
+    // clear the count of recent crashes after a succesful startup when not in
+    // safe mode
+    rv = Preferences::ClearUser(kPrefRecentCrashes);
+    if (NS_FAILED(rv)) NS_WARNING("Could not clear startup crash count.");
+  }
+  nsCOMPtr<nsIPrefService> prefs = Preferences::GetService();
+  // save prefs to disk since we are tracking crashes.  This may be
+  // asynchronous, so a crash could sneak in that we would mistake for
+  // a start up crash. See bug 789945 and bug 1361262.
+  rv = prefs->SavePrefFile(nullptr);
+
+  return rv;
+}
+
+NS_IMETHODIMP
+nsAppStartup::RestartInSafeMode(uint32_t aQuitMode) {
+  PR_SetEnv("MOZ_SAFE_MODE_RESTART=1");
+  bool userAllowedQuit = false;
+  this->Quit(aQuitMode | nsIAppStartup::eRestart, 0, &userAllowedQuit);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppStartup::CreateInstanceWithProfile(nsIToolkitProfile* aProfile) {
+  if (NS_WARN_IF(!aProfile)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  if (NS_WARN_IF(gAbsoluteArgv0Path.IsEmpty())) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIFile> execPath;
+  nsresult rv =
+      NS_NewLocalFile(gAbsoluteArgv0Path, true, getter_AddRefs(execPath));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  nsCOMPtr<nsIProcess> process = do_CreateInstance(NS_PROCESS_CONTRACTID, &rv);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = process->Init(execPath);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  nsAutoCString profileName;
+  rv = aProfile->GetName(profileName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  NS_ConvertUTF8toUTF16 wideName(profileName);
+
+  const char16_t* args[] = {u"-P", wideName.get()};
+  rv = process->Runw(false, args, 2);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  return NS_OK;
+}