Run smooth scroll animations on the compositor when possible

third_party/WebKit/public/platform/WebLayer.h

 /*
  * Copyright (C) 2011 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 142 matching lines @@
 
     // Removes all animations with the given id.
     virtual void removeAnimation(int animationId) = 0;
 
     // Removes all animations with the given id targeting the given property.
     virtual void removeAnimation(int animationId, WebCompositorAnimation::TargetProperty) = 0;
 
     // Pauses all animations with the given id.
     virtual void pauseAnimation(int animationId, double timeOffset) = 0;
 
+    // Aborts all animations with the given id. Different from removeAnimation
+    // in that aborting an animation stops it from affecting both the pending
+    // and active tree.
+    virtual void abortAnimation(int animationId) = 0;
+
     // Returns true if this layer has any active animations - useful for tests.
     virtual bool hasActiveAnimation() = 0;
 
     // If a scroll parent is set, this layer will inherit its parent's scroll
     // delta and offset even though it will not be a descendant of the scroll
     // in the layer hierarchy.
     virtual void setScrollParent(WebLayer*) = 0;
 
     // A layer will not respect any clips established by layers between it and
     // its nearest clipping ancestor. Note, the clip parent must be an ancestor.
@@ skipping 78 matching lines @@
     virtual void setElementId(uint64_t) = 0;
     virtual uint64_t elementId() const = 0;
 
     virtual void setCompositorMutableProperties(uint32_t) = 0;
     virtual uint32_t compositorMutableProperties() const = 0;
 };
 
 } // namespace blink
 
 #endif // WebLayer_h