Defer starting of animations until after compositing update

Source/core/animation/DocumentAnimations.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 32 matching lines @@
 #include "core/rendering/RenderView.h"
 
 namespace WebCore {
 
 namespace {
 
 void updateAnimationTiming(Document& document)
 {
     document.timeline()->serviceAnimations();
     document.transitionTimeline()->serviceAnimations();
-    if (!document.childNeedsStyleRecalc())
-        document.animationClock().unfreeze();
 }
 
-void dispatchAnimationEvents(Document& document)
+} // namespace
+
+void DocumentAnimations::dispatchAnimationEvents(Document& document)
 {
     document.timeline()->dispatchEvents();
     document.transitionTimeline()->dispatchEvents();
 }
 
-void dispatchAnimationEventsAsync(Document& document)
+void DocumentAnimations::dispatchAnimationEventsAsync(Document& document)
 {
     document.timeline()->dispatchEventsAsync();
     document.transitionTimeline()->dispatchEventsAsync();
 }
 
-} // namespace
-
-void DocumentAnimations::serviceOnAnimationFrame(Document& document, double monotonicAnimationStartTime)
+void DocumentAnimations::updateAnimationTimingForAnimationFrame(Document& document, double monotonicAnimationStartTime)
 {
     document.animationClock().updateTime(monotonicAnimationStartTime);
     updateAnimationTiming(document);
-    dispatchAnimationEvents(document);
 }
 
-void DocumentAnimations::serviceBeforeGetComputedStyle(Node& node, CSSPropertyID property)
+void DocumentAnimations::updateAnimationTimingForGetComputedStyle(Node& node, CSSPropertyID property)
 {
     if (!node.isElementNode())
         return;
     const Element& element = toElement(node);
     if (element.document().timeline()->hasOutdatedPlayer()) {
         updateAnimationTiming(element.document());
         return;
     }
     if (const ActiveAnimations* activeAnimations = element.activeAnimations()) {
         if (activeAnimations->hasActiveAnimationsOnCompositor(property))
             updateAnimationTiming(element.document());
     }
 }
 
-void DocumentAnimations::serviceAfterStyleRecalc(Document& document)
+void DocumentAnimations::startPendingAnimations(Document& document)
 {
+    ASSERT(document.lifecycle().state() == DocumentLifecycle::CompositingClean);
     if (document.cssPendingAnimations().startPendingAnimations() && document.view())

[esprehn, 2014/02/25 00:00:48]

You should ASSERT(document().view()) here, it can't be null, the place where you
call this is inside RLC which means the FrameView must exist since the
RenderView still exists.

[dstockwell, 2014/02/25 00:52:03]

Done.

         document.view()->scheduleAnimation();
 
     document.animationClock().unfreeze();
-    dispatchAnimationEventsAsync(document);
 }
 
 } // namespace WebCore