Discard SampledEffects on elements if they are redundant

third_party/WebKit/Source/core/animation/KeyframeEffect.h

 /*
  * 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 54 matching lines @@
 
     bool isKeyframeEffect() const override { return true; }
 
     bool affects(PropertyHandle) const;
     const EffectModel* model() const { return m_model.get(); }
     EffectModel* model() { return m_model.get(); }
     void setModel(EffectModel* model) { m_model = model; }
     Priority priority() const { return m_priority; }
     Element* target() const { return m_target; }
 
+    void notifySampledEffectRemovedFromAnimationStack();
 #if !ENABLE(OILPAN)
     void notifyElementDestroyed();
 #endif
 
     bool isCandidateForAnimationOnCompositor(double animationPlaybackRate) const;
     // Must only be called once.
     bool maybeStartAnimationOnCompositor(int group, double startTime, double timeOffset, double animationPlaybackRate);
     bool hasActiveAnimationsOnCompositor() const;
     bool hasActiveAnimationsOnCompositor(CSSPropertyID) const;
     bool cancelAnimationOnCompositor();
@@ skipping 33 matching lines @@
     Vector<int> m_compositorAnimationIds;
 
     friend class AnimationAnimationV8Test;
 };
 
 DEFINE_TYPE_CASTS(KeyframeEffect, AnimationEffect, animationNode, animationNode->isKeyframeEffect(), animationNode.isKeyframeEffect());
 
 } // namespace blink
 
 #endif // KeyframeEffect_h