Bug 1696158 - Move CanSavePresentation to the parent process. Keep track of various flags for deciding whether to put a page in BFCache. r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D110231

dom/base/Document.cpp

@@ -6783,6 +6783,17 @@ void Document::DeletePresShell() {
   mDesignModeSheetAdded = false;
 }
 
+void Document::DisallowBFCaching() {
+  NS_ASSERTION(!mBFCacheEntry, "We're already in the bfcache!");
+  if (!mBFCacheDisallowed) {
+    WindowGlobalChild* wgc = GetWindowGlobalChild();
+    if (wgc) {
+      wgc->BlockBFCacheFor(BFCacheStatus::NOT_ALLOWED);
+    }
+  }
+  mBFCacheDisallowed = true;
+}
+
 void Document::SetBFCacheEntry(nsIBFCacheEntry* aEntry) {
   MOZ_ASSERT(IsBFCachingAllowed() || !aEntry, "You should have checked!");
 
@@ -11857,6 +11868,12 @@ void Document::GetReadyState(nsAString& aReadyState) const {
 
 void Document::SuppressEventHandling(uint32_t aIncrease) {
   mEventsSuppressed += aIncrease;
+  if (mEventsSuppressed == aIncrease) {
+    WindowGlobalChild* wgc = GetWindowGlobalChild();
+    if (wgc) {
+      wgc->BlockBFCacheFor(BFCacheStatus::EVENT_HANDLING_SUPPRESSED);
+    }
+  }
   UpdateFrameRequestCallbackSchedulingState();
   for (uint32_t i = 0; i < aIncrease; ++i) {
     ScriptLoader()->AddExecuteBlocker();
@@ -12255,6 +12272,11 @@ void Document::UnsuppressEventHandlingAndFireEvents(bool aFireEvents) {
   }
 
   if (!EventHandlingSuppressed()) {
+    WindowGlobalChild* wgc = GetWindowGlobalChild();
+    if (wgc) {
+      wgc->UnblockBFCacheFor(BFCacheStatus::EVENT_HANDLING_SUPPRESSED);
+    }
+
     MOZ_ASSERT(NS_IsMainThread());
     nsTArray<RefPtr<net::ChannelEventQueue>> queues =
         std::move(mSuspendedQueues);
@@ -17231,4 +17253,23 @@ void Document::DisableChildElementInPictureInPictureMode() {
   MOZ_ASSERT(mPictureInPictureChildElementCount >= 0);
 }
 
+void Document::AddMediaElementWithMSE() {
+  if (mMediaElementWithMSECount++ == 0) {
+    WindowGlobalChild* wgc = GetWindowGlobalChild();
+    if (wgc) {
+      wgc->BlockBFCacheFor(BFCacheStatus::CONTAINS_MSE_CONTENT);
+    }
+  }
+}
+
+void Document::RemoveMediaElementWithMSE() {
+  MOZ_ASSERT(mMediaElementWithMSECount > 0);
+  if (--mMediaElementWithMSECount == 0) {
+    WindowGlobalChild* wgc = GetWindowGlobalChild();
+    if (wgc) {
+      wgc->UnblockBFCacheFor(BFCacheStatus::CONTAINS_MSE_CONTENT);
+    }
+  }
+}
+
 }  // namespace mozilla::dom

dom/base/Document.h

@@ -1201,10 +1201,7 @@ class Document : public nsINode,
 
   // Instead using this method, what you probably want is
   // RemoveFromBFCacheSync() as we do in MessagePort and BroadcastChannel.
-  void DisallowBFCaching() {
+  void DisallowBFCaching();
-    NS_ASSERTION(!mBFCacheEntry, "We're already in the bfcache!");
-    mBFCacheDisallowed = true;
-  }
 
   bool IsBFCachingAllowed() const { return !mBFCacheDisallowed; }
 
@@ -1520,6 +1517,9 @@ class Document : public nsINode,
 
   bool ShouldIncludeInTelemetry(bool aAllowExtensionURIs);
 
+  void AddMediaElementWithMSE();
+  void RemoveMediaElementWithMSE();
+
  protected:
   friend class nsUnblockOnloadEvent;
 
@@ -5233,6 +5233,8 @@ class Document : public nsINode,
   int32_t mNextFormNumber;
   int32_t mNextControlNumber;
 
+  uint32_t mMediaElementWithMSECount = 0;
+
   // Scope preloads per document.  This is used by speculative loading as well.
   PreloadService mPreloadService;
 

dom/base/nsGlobalWindowInner.cpp

@@ -939,8 +939,7 @@ nsGlobalWindowInner::nsGlobalWindowInner(nsGlobalWindowOuter* aOuterWindow,
       mAreDialogsEnabled(true),
       mObservingRefresh(false),
       mIteratingDocumentFlushedResolvers(false),
-      mCanSkipCCGeneration(0),
+      mCanSkipCCGeneration(0) {
-      mBeforeUnloadListenerCount(0) {
   mIsInnerWindow = true;
 
   AssertIsOnMainThread();
@@ -2635,11 +2634,17 @@ bool nsPIDOMWindowInner::HasActivePeerConnections() {
 void nsPIDOMWindowInner::AddMediaKeysInstance(MediaKeys* aMediaKeys) {
   MOZ_ASSERT(NS_IsMainThread());
   mMediaKeysInstances.AppendElement(aMediaKeys);
+  if (mWindowGlobalChild && mMediaKeysInstances.Length() == 1) {
+    mWindowGlobalChild->BlockBFCacheFor(BFCacheStatus::CONTAINS_EME_CONTENT);
+  }
 }
 
 void nsPIDOMWindowInner::RemoveMediaKeysInstance(MediaKeys* aMediaKeys) {
   MOZ_ASSERT(NS_IsMainThread());
   mMediaKeysInstances.RemoveElement(aMediaKeys);
+  if (mWindowGlobalChild && mMediaKeysInstances.IsEmpty()) {
+    mWindowGlobalChild->UnblockBFCacheFor(BFCacheStatus::CONTAINS_EME_CONTENT);
+  }
 }
 
 bool nsPIDOMWindowInner::HasActiveMediaKeysInstance() {
@@ -5460,6 +5465,10 @@ void nsGlobalWindowInner::Suspend(bool aIncludeSubWindows) {
     return;
   }
 
+  if (mWindowGlobalChild) {
+    mWindowGlobalChild->BlockBFCacheFor(BFCacheStatus::SUSPENDED);
+  }
+
   nsCOMPtr<nsIDeviceSensors> ac = do_GetService(NS_DEVICE_SENSORS_CONTRACTID);
   if (ac) {
     for (uint32_t i = 0; i < mEnabledSensors.Length(); i++)
@@ -5546,6 +5555,10 @@ void nsGlobalWindowInner::Resume(bool aIncludeSubWindows) {
        mSharedWorkers.ForwardRange()) {
     pinnedWorker->Resume();
   }
+
+  if (mWindowGlobalChild) {
+    mWindowGlobalChild->UnblockBFCacheFor(BFCacheStatus::SUSPENDED);
+  }
 }
 
 bool nsGlobalWindowInner::IsSuspended() const {
@@ -6462,10 +6475,16 @@ void nsGlobalWindowInner::EventListenerAdded(nsAtom* aType) {
     mHasVRDisplayActivateEvents = true;
   }
 
-  if (aType == nsGkAtoms::onbeforeunload && mWindowGlobalChild &&
+  if ((aType == nsGkAtoms::onunload || aType == nsGkAtoms::onbeforeunload) &&
-      (!mDoc || !(mDoc->GetSandboxFlags() & SANDBOXED_MODALS))) {
+      mWindowGlobalChild) {
-    mWindowGlobalChild->BeforeUnloadAdded();
+    if (++mUnloadOrBeforeUnloadListenerCount == 1) {
-    MOZ_ASSERT(mWindowGlobalChild->BeforeUnloadListeners() > 0);
+      mWindowGlobalChild->BlockBFCacheFor(BFCacheStatus::UNLOAD_LISTENER);
+    }
+    if (aType == nsGkAtoms::onbeforeunload &&
+        (!mDoc || !(mDoc->GetSandboxFlags() & SANDBOXED_MODALS))) {
+      mWindowGlobalChild->BeforeUnloadAdded();
+      MOZ_ASSERT(mWindowGlobalChild->BeforeUnloadListeners() > 0);
+    }
   }
 
   // We need to initialize localStorage in order to receive notifications.
@@ -6484,10 +6503,17 @@ void nsGlobalWindowInner::EventListenerAdded(nsAtom* aType) {
 }
 
 void nsGlobalWindowInner::EventListenerRemoved(nsAtom* aType) {
-  if (aType == nsGkAtoms::onbeforeunload && mWindowGlobalChild &&
+  if ((aType == nsGkAtoms::onunload || aType == nsGkAtoms::onbeforeunload) &&
-      (!mDoc || !(mDoc->GetSandboxFlags() & SANDBOXED_MODALS))) {
+      mWindowGlobalChild) {
-    mWindowGlobalChild->BeforeUnloadRemoved();
+    MOZ_ASSERT(mUnloadOrBeforeUnloadListenerCount > 0);
-    MOZ_ASSERT(mWindowGlobalChild->BeforeUnloadListeners() >= 0);
+    if (--mUnloadOrBeforeUnloadListenerCount == 0) {
+      mWindowGlobalChild->UnblockBFCacheFor(BFCacheStatus::UNLOAD_LISTENER);
+    }
+    if (aType == nsGkAtoms::onbeforeunload &&
+        (!mDoc || !(mDoc->GetSandboxFlags() & SANDBOXED_MODALS))) {
+      mWindowGlobalChild->BeforeUnloadRemoved();
+      MOZ_ASSERT(mWindowGlobalChild->BeforeUnloadListeners() >= 0);
+    }
   }
 
   if (aType == nsGkAtoms::onstorage) {
@@ -6511,6 +6537,9 @@ void nsGlobalWindowInner::NotifyHasXRSession() {
     // has been called, including mVREventObserver.
     return;
   }
+  if (mWindowGlobalChild && !mHasXRSession) {
+    mWindowGlobalChild->BlockBFCacheFor(BFCacheStatus::HAS_USED_VR);
+  }
   mHasXRSession = true;
   EnableVRUpdates();
 }

dom/base/nsGlobalWindowInner.h

@@ -1473,7 +1473,9 @@ class nsGlobalWindowInner final : public mozilla::dom::EventTarget,
 
   RefPtr<mozilla::dom::VREventObserver> mVREventObserver;
 
-  int64_t mBeforeUnloadListenerCount;
+  // The number of unload and beforeunload even listeners registered on this
+  // window.
+  uint64_t mUnloadOrBeforeUnloadListenerCount = 0;
 
   RefPtr<mozilla::dom::IntlUtils> mIntlUtils;
 

dom/html/HTMLMediaElement.cpp

@@ -86,6 +86,7 @@
 #include "mozilla/dom/VideoTrack.h"
 #include "mozilla/dom/VideoTrackList.h"
 #include "mozilla/dom/WakeLock.h"
+#include "mozilla/dom/WindowGlobalChild.h"
 #include "mozilla/dom/power/PowerManagerService.h"
 #include "mozilla/net/UrlClassifierFeatureFactory.h"
 #include "nsAttrValueInlines.h"
@@ -2239,6 +2240,10 @@ void HTMLMediaElement::AbortExistingLoads() {
     EndSrcMediaStreamPlayback();
   }
 
+  if (mMediaSource) {
+    OwnerDoc()->RemoveMediaElementWithMSE();
+  }
+
   RemoveMediaElementFromURITable();
   mLoadingSrcTriggeringPrincipal = nullptr;
   DDLOG(DDLogCategory::Property, "loading_src", "");
@@ -2549,6 +2554,10 @@ void HTMLMediaElement::SelectResource() {
           !mIsLoadingFromSourceChildren,
           "Should think we're not loading from source children by default");
 
+      if (!mMediaSource) {
+        OwnerDoc()->AddMediaElementWithMSE();
+      }
+
       RemoveMediaElementFromURITable();
       if (!mSrcMediaSource) {
         mLoadingSrc = uri;
@@ -2812,6 +2821,10 @@ void HTMLMediaElement::LoadFromSourceChildren() {
       return;
     }
 
+    if (!mMediaSource) {
+      OwnerDoc()->AddMediaElementWithMSE();
+    }
+
     RemoveMediaElementFromURITable();
     mLoadingSrc = uri;
     mLoadingSrcTriggeringPrincipal = childSrc->GetSrcTriggeringPrincipal();
@@ -7652,6 +7665,15 @@ bool HTMLMediaElement::IsBeingUsedInPictureInPictureMode() const {
   return static_cast<const HTMLVideoElement*>(this)->IsCloningElementVisually();
 }
 
+void HTMLMediaElement::NodeInfoChanged(Document* aOldDoc) {
+  if (mMediaSource) {
+    OwnerDoc()->AddMediaElementWithMSE();
+    aOldDoc->RemoveMediaElementWithMSE();
+  }
+
+  nsGenericHTMLElement::NodeInfoChanged(aOldDoc);
+}
+
 }  // namespace mozilla::dom
 
 #undef LOG

dom/html/HTMLMediaElement.h

@@ -192,6 +192,8 @@ class HTMLMediaElement : public nsGenericHTMLElement,
   // EventTarget
   void GetEventTargetParent(EventChainPreVisitor& aVisitor) override;
 
+  void NodeInfoChanged(Document* aOldDoc) override;
+
   virtual bool ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
                               const nsAString& aValue,
                               nsIPrincipal* aMaybeScriptedPrincipal,

dom/ipc/PWindowGlobal.ipdl

@@ -181,6 +181,11 @@ parent:
 
   async ResetSessionStore(uint32_t aEpoch);
 
+  // Add the flags in aOnFlags to the current BFCache status and remove the
+  // flags in aOffFlags from the current BFCache status. See the BFCacheStatus
+  // enum for the valid flags.
+  async UpdateBFCacheStatus(uint16_t aOnFlags, uint16_t aOffFlags);
+
   async Destroy();
 };
 

dom/ipc/WindowGlobalChild.cpp

@@ -671,6 +671,14 @@ bool WindowGlobalChild::SameOriginWithTop() {
   return IsSameOriginWith(WindowContext()->TopWindowContext());
 }
 
+void WindowGlobalChild::UnblockBFCacheFor(BFCacheStatus aStatus) {
+  SendUpdateBFCacheStatus(0, aStatus);
+}
+
+void WindowGlobalChild::BlockBFCacheFor(BFCacheStatus aStatus) {
+  SendUpdateBFCacheStatus(aStatus, 0);
+}
+
 WindowGlobalChild::~WindowGlobalChild() = default;
 
 JSObject* WindowGlobalChild::WrapObject(JSContext* aCx,

dom/ipc/WindowGlobalChild.h

@@ -12,6 +12,7 @@
 #include "mozilla/dom/PWindowGlobalChild.h"
 #include "nsRefPtrHashtable.h"
 #include "nsWrapperCache.h"
+#include "mozilla/dom/Document.h"
 #include "mozilla/dom/WindowGlobalActor.h"
 
 class nsGlobalWindowInner;
@@ -132,6 +133,9 @@ class WindowGlobalChild final : public WindowGlobalActor,
   void SetSessionStoreDataCollector(SessionStoreDataCollector* aCollector);
   SessionStoreDataCollector* GetSessionStoreDataCollector() const;
 
+  void UnblockBFCacheFor(BFCacheStatus aStatus);
+  void BlockBFCacheFor(BFCacheStatus aStatus);
+
  protected:
   const nsACString& GetRemoteType() override;
 

dom/ipc/WindowGlobalParent.cpp

@@ -70,6 +70,7 @@
 using namespace mozilla::ipc;
 using namespace mozilla::dom::ipc;
 
+extern mozilla::LazyLogModule gSHIPBFCacheLog;
 extern mozilla::LazyLogModule gUseCountersLog;
 
 namespace mozilla::dom {
@@ -1315,6 +1316,59 @@ mozilla::ipc::IPCResult WindowGlobalParent::RecvRequestRestoreTabContent() {
   return IPC_OK();
 }
 
+nsCString BFCacheStatusToString(uint16_t aFlags) {
+  if (aFlags == 0) {
+    return "0"_ns;
+  }
+
+  nsCString flags;
+#define ADD_BFCACHESTATUS_TO_STRING(_flag) \
+  if (aFlags & BFCacheStatus::_flag) {     \
+    if (!flags.IsEmpty()) {                \
+      flags.Append('|');                   \
+    }                                      \
+    flags.AppendLiteral(#_flag);           \
+    aFlags &= ~BFCacheStatus::_flag;       \
+  }
+
+  ADD_BFCACHESTATUS_TO_STRING(NOT_ALLOWED);
+  ADD_BFCACHESTATUS_TO_STRING(EVENT_HANDLING_SUPPRESSED);
+  ADD_BFCACHESTATUS_TO_STRING(SUSPENDED);
+  ADD_BFCACHESTATUS_TO_STRING(UNLOAD_LISTENER);
+  ADD_BFCACHESTATUS_TO_STRING(REQUEST);
+  ADD_BFCACHESTATUS_TO_STRING(ACTIVE_GET_USER_MEDIA);
+  ADD_BFCACHESTATUS_TO_STRING(ACTIVE_PEER_CONNECTION);
+  ADD_BFCACHESTATUS_TO_STRING(CONTAINS_EME_CONTENT);
+  ADD_BFCACHESTATUS_TO_STRING(CONTAINS_MSE_CONTENT);
+  ADD_BFCACHESTATUS_TO_STRING(HAS_ACTIVE_SPEECH_SYNTHESIS);
+  ADD_BFCACHESTATUS_TO_STRING(HAS_USED_VR);
+  ADD_BFCACHESTATUS_TO_STRING(CONTAINS_REMOTE_SUBFRAMES);
+  ADD_BFCACHESTATUS_TO_STRING(NOT_ONLY_TOPLEVEL_IN_BCG);
+
+#undef ADD_BFCACHESTATUS_TO_STRING
+
+  MOZ_ASSERT(aFlags == 0,
+             "Missing stringification for enum value in BFCacheStatus.");
+  return flags;
+}
+
+mozilla::ipc::IPCResult WindowGlobalParent::RecvUpdateBFCacheStatus(
+    const uint16_t& aOnFlags, const uint16_t& aOffFlags) {
+  if (MOZ_UNLIKELY(MOZ_LOG_TEST(gSHIPBFCacheLog, LogLevel::Debug))) {
+    nsAutoCString uri("[no uri]");
+    if (mDocumentURI) {
+      uri = mDocumentURI->GetSpecOrDefault();
+    }
+    MOZ_LOG(gSHIPBFCacheLog, LogLevel::Debug,
+            ("Setting BFCache flags for %s +(%s) -(%s)", uri.get(),
+             BFCacheStatusToString(aOnFlags).get(),
+             BFCacheStatusToString(aOffFlags).get()));
+  }
+  mBFCacheStatus |= aOnFlags;
+  mBFCacheStatus &= ~aOffFlags;
+  return IPC_OK();
+}
+
 void WindowGlobalParent::ActorDestroy(ActorDestroyReason aWhy) {
   if (mPageUseCountersWindow) {
     mPageUseCountersWindow->FinishAccumulatingPageUseCounters();

dom/ipc/WindowGlobalParent.h

@@ -280,6 +280,9 @@ class WindowGlobalParent final : public WindowContext,
 
   mozilla::ipc::IPCResult RecvResetSessionStore(uint32_t aEpoch);
 
+  mozilla::ipc::IPCResult RecvUpdateBFCacheStatus(const uint16_t& aOnFlags,
+                                                  const uint16_t& aOffFlags);
+
  private:
   WindowGlobalParent(CanonicalBrowsingContext* aBrowsingContext,
                      uint64_t aInnerWindowId, uint64_t aOuterWindowId,
@@ -352,6 +355,8 @@ class WindowGlobalParent final : public WindowContext,
   // Whether we have sent our page use counters, and so should ignore any
   // subsequent ExpectPageUseCounters calls.
   bool mSentPageUseCounters = false;
+
+  uint16_t mBFCacheStatus = 0;
 };
 
 }  // namespace dom

dom/media/MediaManager.cpp

@@ -38,6 +38,7 @@
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/UserActivation.h"
 #include "mozilla/dom/WindowContext.h"
+#include "mozilla/dom/WindowGlobalChild.h"
 #include "mozilla/ipc/BackgroundChild.h"
 #include "mozilla/media/MediaChild.h"
 #include "mozilla/media/MediaTaskUtils.h"
@@ -164,6 +165,7 @@ class GetUserMediaStreamTask;
 class LocalTrackSource;
 class SelectAudioOutputTask;
 
+using dom::BFCacheStatus;
 using dom::CallerType;
 using dom::ConstrainDOMStringParameters;
 using dom::ConstrainDoubleRange;
@@ -191,6 +193,7 @@ using dom::OwningStringOrStringSequenceOrConstrainDOMStringParameters;
 using dom::Promise;
 using dom::Sequence;
 using dom::UserActivation;
+using dom::WindowGlobalChild;
 using media::NewRunnableFrom;
 using media::NewTaskFrom;
 using media::Refcountable;
@@ -3411,9 +3414,21 @@ void MediaManager::AddWindowID(uint64_t aWindowId,
   aListener->MuteOrUnmuteCameras(mCamerasMuted);
   aListener->MuteOrUnmuteMicrophones(mMicrophonesMuted);
   GetActiveWindows()->InsertOrUpdate(aWindowId, std::move(aListener));
+
+  RefPtr<WindowGlobalChild> wgc =
+      WindowGlobalChild::GetByInnerWindowId(aWindowId);
+  if (wgc) {
+    wgc->BlockBFCacheFor(BFCacheStatus::ACTIVE_GET_USER_MEDIA);
+  }
 }
 
 void MediaManager::RemoveWindowID(uint64_t aWindowId) {
+  RefPtr<WindowGlobalChild> wgc =
+      WindowGlobalChild::GetByInnerWindowId(aWindowId);
+  if (wgc) {
+    wgc->UnblockBFCacheFor(BFCacheStatus::ACTIVE_GET_USER_MEDIA);
+  }
+
   mActiveWindows.Remove(aWindowId);
 
   // get outer windowID

dom/media/webspeech/synth/SpeechSynthesis.cpp

@@ -11,6 +11,7 @@
 #include "mozilla/dom/Element.h"
 
 #include "mozilla/dom/SpeechSynthesisBinding.h"
+#include "mozilla/dom/WindowGlobalChild.h"
 #include "SpeechSynthesis.h"
 #include "nsContentUtils.h"
 #include "nsSynthVoiceRegistry.h"
@@ -118,11 +119,18 @@ void SpeechSynthesis::Speak(SpeechSynthesisUtterance& aUtterance) {
 
   mSpeechQueue.AppendElement(&aUtterance);
 
-  // If we only have one item in the queue, we aren't pre-paused, and
+  if (mSpeechQueue.Length() == 1) {
-  // we have voices available, speak it.
+    RefPtr<WindowGlobalChild> wgc =
-  if (mSpeechQueue.Length() == 1 && !mCurrentTask && !mHoldQueue &&
+        WindowGlobalChild::GetByInnerWindowId(mInnerID);
-      HasVoices()) {
+    if (wgc) {
-    AdvanceQueue();
+      wgc->BlockBFCacheFor(BFCacheStatus::HAS_ACTIVE_SPEECH_SYNTHESIS);
+    }
+
+    // If we only have one item in the queue, we aren't pre-paused, and
+    // we have voices available, speak it.
+    if (!mCurrentTask && !mHoldQueue && HasVoices()) {
+      AdvanceQueue();
+    }
   }
 }
 
@@ -201,6 +209,13 @@ void SpeechSynthesis::OnEnd(const nsSpeechTask* aTask) {
 
   if (!mSpeechQueue.IsEmpty()) {
     mSpeechQueue.RemoveElementAt(0);
+    if (mSpeechQueue.IsEmpty()) {
+      RefPtr<WindowGlobalChild> wgc =
+          WindowGlobalChild::GetByInnerWindowId(mInnerID);
+      if (wgc) {
+        wgc->UnblockBFCacheFor(BFCacheStatus::HAS_ACTIVE_SPEECH_SYNTHESIS);
+      }
+    }
   }
 
   mCurrentTask = nullptr;