Bug 1958970 - Change animation event set-up to match the spec better. r=smaug,firefox-animation-reviewers,boris

Deal with events per-document like the spec. This also ensures that view
transition rendering suppressions and such work for this rendering
phase.

Differential Revision: https://phabricator.services.mozilla.com/D244670

dom/animation/AnimationEventDispatcher.cpp

@@ -100,35 +100,36 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(AnimationEventDispatcher)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 
 void AnimationEventDispatcher::Disconnect() {
-  if (mIsObserving) {
+  ClearEventQueue();
-    MOZ_ASSERT(mPresContext && mPresContext->RefreshDriver(),
-               "The pres context and the refresh driver should be still "
-               "alive if we haven't disassociated from the refresh driver");
-    mPresContext->RefreshDriver()->CancelPendingAnimationEvents(this);
-    mIsObserving = false;
-  }
   mPresContext = nullptr;
 }
 
 void AnimationEventDispatcher::QueueEvent(AnimationEventInfo&& aEvent) {
+  const bool wasEmpty = mPendingEvents.IsEmpty();
   mPendingEvents.AppendElement(std::move(aEvent));
-  mIsSorted = false;
+  mIsSorted = !wasEmpty;
-  ScheduleDispatch();
+  if (wasEmpty) {
+    ScheduleDispatch();
+  }
 }
 
 void AnimationEventDispatcher::QueueEvents(
     nsTArray<AnimationEventInfo>&& aEvents) {
+  if (aEvents.IsEmpty()) {
+    return;
+  }
+  const bool wasEmpty = mPendingEvents.IsEmpty();
   mPendingEvents.AppendElements(std::move(aEvents));
   mIsSorted = false;
-  ScheduleDispatch();
+  if (wasEmpty) {
+    ScheduleDispatch();
+  }
 }
 
 void AnimationEventDispatcher::ScheduleDispatch() {
   MOZ_ASSERT(mPresContext, "The pres context should be valid");
-  if (!mIsObserving) {
+  mPresContext->RefreshDriver()->ScheduleRenderingPhase(
-    mPresContext->RefreshDriver()->ScheduleAnimationEventDispatch(this);
+      RenderingPhase::UpdateAnimationsAndSendEvents);
-    mIsObserving = true;
-  }
 }
 
 void AnimationEventInfo::MaybeAddMarker() const {

dom/animation/AnimationEventDispatcher.h

@@ -236,7 +236,7 @@ struct AnimationEventInfo {
 class AnimationEventDispatcher final {
  public:
   explicit AnimationEventDispatcher(nsPresContext* aPresContext)
-      : mPresContext(aPresContext), mIsSorted(true), mIsObserving(false) {}
+      : mPresContext(aPresContext), mIsSorted(true) {}
 
   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AnimationEventDispatcher)
   NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(AnimationEventDispatcher)
@@ -249,7 +249,6 @@ class AnimationEventDispatcher final {
   // This will call SortEvents automatically if it has not already been
   // called.
   void DispatchEvents() {
-    mIsObserving = false;
     if (!mPresContext || mPendingEvents.IsEmpty()) {
       return;
     }
@@ -288,15 +287,7 @@ class AnimationEventDispatcher final {
   }
 
  private:
-#ifndef DEBUG
   ~AnimationEventDispatcher() = default;
-#else
-  ~AnimationEventDispatcher() {
-    MOZ_ASSERT(!mIsObserving,
-               "AnimationEventDispatcher should have disassociated from "
-               "nsRefreshDriver");
-  }
-#endif
 
   // Sort all pending CSS animation/transition events by scheduled event time
   // and composite order.
@@ -324,7 +315,6 @@ class AnimationEventDispatcher final {
   using EventArray = nsTArray<AnimationEventInfo>;
   EventArray mPendingEvents;
   bool mIsSorted;
-  bool mIsObserving;
 };
 
 }  // namespace mozilla

dom/base/Document.cpp

@@ -7416,7 +7416,7 @@ bool Document::IsRenderingSuppressed() const {
   }
   // The user agent believes that updating the rendering of doc's node navigable
   // would have no visible effect.
-  if (!IsEventHandlingEnabled()) {
+  if (!IsEventHandlingEnabled() && !IsBeingUsedAsImage()) {
     return true;
   }
   if (!mPresShell || !mPresShell->DidInitialize()) {

layout/base/PresShell.cpp

@@ -18,6 +18,7 @@
 #include "gfxUtils.h"
 #include "MobileViewportManager.h"
 #include "mozilla/AccessibleCaretEventHub.h"
+#include "mozilla/AnimationEventDispatcher.h"
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/Assertions.h"
 #include "mozilla/Attributes.h"
@@ -1349,7 +1350,7 @@ void PresShell::Destroy() {
   }
 
   if (mPresContext) {
-    rd->CancelPendingAnimationEvents(mPresContext->AnimationEventDispatcher());
+    mPresContext->AnimationEventDispatcher()->ClearEventQueue();
   }
 
   // Revoke any pending events.  We need to do this and cancel pending reflows

layout/base/nsRefreshDriver.cpp

@@ -1860,8 +1860,7 @@ bool nsRefreshDriver::HasObservers() const {
   }
 
   return (mViewManagerFlushIsPending && !mThrottled) ||
-         !mStyleFlushObservers.IsEmpty() ||
+         !mStyleFlushObservers.IsEmpty() || !mEarlyRunners.IsEmpty();
-         !mEarlyRunners.IsEmpty();
 }
 
 void nsRefreshDriver::AppendObserverDescriptionsToString(
@@ -2126,7 +2125,7 @@ void nsRefreshDriver::DetermineProximityToViewportAndNotifyResizeObservers() {
       Filter);
 }
 
-static CallState UpdateAndReduceAnimations(Document& aDocument) {
+static void UpdateAndReduceAnimations(Document& aDocument) {
   for (DocumentTimeline* tl :
        ToTArray<AutoTArray<RefPtr<DocumentTimeline>, 32>>(
            aDocument.Timelines())) {
@@ -2138,39 +2137,6 @@ static CallState UpdateAndReduceAnimations(Document& aDocument) {
       pc->EffectCompositor()->ReduceAnimations();
     }
   }
-  aDocument.EnumerateSubDocuments(UpdateAndReduceAnimations);
-  return CallState::Continue;
-}
-
-void nsRefreshDriver::UpdateAnimationsAndSendEvents() {
-  if (!mPresContext) {
-    return;
-  }
-
-  {
-    // Animation updates may queue Promise resolution microtasks. We shouldn't
-    // run these, however, until we have fully updated the animation state. As
-    // per the "update animations and send events" procedure[1], we should
-    // remove replaced animations and then run these microtasks before
-    // dispatching the corresponding animation events.
-    //
-    // [1]:
-    // https://drafts.csswg.org/web-animations-1/#update-animations-and-send-events
-    nsAutoMicroTask mt;
-    RefPtr doc = mPresContext->Document();
-    UpdateAndReduceAnimations(*doc);
-  }
-
-  // Hold all AnimationEventDispatcher in mAnimationEventFlushObservers as
-  // a RefPtr<> array since each AnimationEventDispatcher might be destroyed
-  // during processing the previous dispatcher.
-  AutoTArray<RefPtr<AnimationEventDispatcher>, 16> dispatchers;
-  dispatchers.AppendElements(mAnimationEventFlushObservers);
-  mAnimationEventFlushObservers.Clear();
-
-  for (auto& dispatcher : dispatchers) {
-    dispatcher->DispatchEvents();
-  }
 }
 
 void nsRefreshDriver::RunVideoFrameCallbacks(
@@ -2569,10 +2535,27 @@ void nsRefreshDriver::Tick(VsyncId aId, TimeStamp aNowTime,
       });
 
   // Step 11. For each doc of docs, update animations and send events for doc.
-  RunRenderingPhaseLegacy(RenderingPhase::UpdateAnimationsAndSendEvents,
+  RunRenderingPhase(RenderingPhase::UpdateAnimationsAndSendEvents,
-                          [&]() MOZ_CAN_RUN_SCRIPT_BOUNDARY_LAMBDA {
+                    [&](Document& aDoc) MOZ_CAN_RUN_SCRIPT_BOUNDARY_LAMBDA {
-                            UpdateAnimationsAndSendEvents();
+                      {
-                          });
+                        // Animation updates may queue Promise resolution
+                        // microtasks. We shouldn't run these, however, until we
+                        // have fully updated the animation state. As per the
+                        // "update animations and send events" procedure[1], we
+                        // should remove replaced animations and then run these
+                        // microtasks before dispatching the corresponding
+                        // animation events.
+                        //
+                        // [1]:
+                        // https://drafts.csswg.org/web-animations-1/#update-animations-and-send-events
+                        nsAutoMicroTask mt;
+                        UpdateAndReduceAnimations(aDoc);
+                      }
+                      if (RefPtr pc = aDoc.GetPresContext()) {
+                        RefPtr dispatcher = pc->AnimationEventDispatcher();
+                        dispatcher->DispatchEvents();
+                      }
+                    });
 
   // Step 12. For each doc of docs, run the fullscreen steps for doc.
   RunRenderingPhaseLegacy(
@@ -3078,13 +3061,6 @@ void nsRefreshDriver::CancelPendingFullscreenEvents(Document* aDocument) {
   }
 }
 
-void nsRefreshDriver::CancelPendingAnimationEvents(
-    AnimationEventDispatcher* aDispatcher) {
-  MOZ_ASSERT(aDispatcher);
-  aDispatcher->ClearEventQueue();
-  mAnimationEventFlushObservers.RemoveElement(aDispatcher);
-}
-
 /* static */
 TimeStamp nsRefreshDriver::GetIdleDeadlineHint(TimeStamp aDefault,
                                                IdleCheck aCheckType) {

layout/base/nsRefreshDriver.h

@@ -192,24 +192,6 @@ class nsRefreshDriver final : public mozilla::layers::TransactionIdAllocator,
    */
   void CancelPendingFullscreenEvents(Document* aDocument);
 
-  /**
-   * Queue new animation events to dispatch in next tick.
-   */
-  void ScheduleAnimationEventDispatch(
-      mozilla::AnimationEventDispatcher* aDispatcher) {
-    NS_ASSERTION(!mAnimationEventFlushObservers.Contains(aDispatcher),
-                 "Double-adding animation event flush observer");
-    mAnimationEventFlushObservers.AppendElement(aDispatcher);
-    ScheduleRenderingPhase(
-        mozilla::RenderingPhase::UpdateAnimationsAndSendEvents);
-  }
-
-  /**
-   * Cancel all pending animation events associated with |aDispatcher|.
-   */
-  void CancelPendingAnimationEvents(
-      mozilla::AnimationEventDispatcher* aDispatcher);
-
   /**
    * Schedule a frame visibility update "soon", subject to the heuristics and
    * throttling we apply to visibility updates.
@@ -441,7 +423,6 @@ class nsRefreshDriver final : public mozilla::layers::TransactionIdAllocator,
   };
   using ObserverArray = nsTObserverArray<ObserverData>;
   void RunFullscreenSteps();
-  void UpdateAnimationsAndSendEvents();
 
   MOZ_CAN_RUN_SCRIPT
   void RunVideoAndFrameRequestCallbacks(mozilla::TimeStamp aNowTime);
@@ -645,8 +626,6 @@ class nsRefreshDriver final : public mozilla::layers::TransactionIdAllocator,
   nsTObserverArray<nsAPostRefreshObserver*> mPostRefreshObservers;
   nsTArray<mozilla::UniquePtr<mozilla::PendingFullscreenEvent>>
       mPendingFullscreenEvents;
-  AutoTArray<mozilla::AnimationEventDispatcher*, 16>
-      mAnimationEventFlushObservers;
 
   // nsPresContexts which `NotifyContentfulPaint` have been called,
   // however the corresponding paint doesn't come from a regular

testing/web-platform/meta/css/css-view-transitions/no-css-animation-while-render-blocked.html.ini

@@ -1,8 +0,0 @@
-[no-css-animation-while-render-blocked.html]
-  expected:
-    if (os == "mac") and debug: [CRASH, OK]
-    [OK, CRASH]
-  [CSS animation is blocked until prepare callback]
-    expected:
-      if (processor == "x86") and (os == "win") and not debug: [PASS, FAIL]
-      FAIL