Run smooth scroll animations on the compositor when possible

cc/blink/web_layer_impl.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_BLINK_WEB_LAYER_IMPL_H_
 #define CC_BLINK_WEB_LAYER_IMPL_H_
 
 #include <string>
 #include <utility>
 
@@ skipping 91 matching lines @@
   blink::WebColor backgroundColor() const override;
   void setFilters(const blink::WebFilterOperations& filters) override;
   void setBackgroundFilters(const blink::WebFilterOperations& filters) override;
   void setAnimationDelegate(
       blink::WebCompositorAnimationDelegate* delegate) override;
   bool addAnimation(blink::WebCompositorAnimation* animation) override;
   void removeAnimation(int animation_id) override;
   void removeAnimation(int animation_id,
                        blink::WebCompositorAnimation::TargetProperty) override;
   void pauseAnimation(int animation_id, double time_offset) override;
+  void abortAnimation(int animation_id) override;
   bool hasActiveAnimation() override;
   void setForceRenderSurface(bool force) override;
   void setScrollPositionDouble(blink::WebDoublePoint position) override;
   blink::WebDoublePoint scrollPositionDouble() const override;
   void setScrollCompensationAdjustment(blink::WebDoublePoint position) override;
   void setScrollClipLayer(blink::WebLayer* clip_layer) override;
   bool scrollable() const override;
   void setUserScrollable(bool horizontal, bool vertical) override;
   bool userScrollableHorizontal() const override;
   bool userScrollableVertical() const override;
@@ skipping 40 matching lines @@
 
  private:
   scoped_ptr<WebToCCAnimationDelegateAdapter> animation_delegate_adapter_;
 
   DISALLOW_COPY_AND_ASSIGN(WebLayerImpl);
 };
 
 }  // namespace cc_blink
 
 #endif  // CC_BLINK_WEB_LAYER_IMPL_H_