cc : Track opacity animation changes on effect tree

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 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_TREES_LAYER_TREE_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 262 matching lines @@
                                   ElementListType list_type,
                                   const gfx::Transform& transform) override;
   void SetElementScrollOffsetMutated(
       ElementId element_id,
       ElementListType list_type,
       const gfx::ScrollOffset& scroll_offset) override;
   void ElementTransformIsPotentiallyAnimatingChanged(
       ElementId element_id,
       ElementListType list_type,
       bool is_animating) override;
+  void ElementOpacityIsAnimatingChanged(ElementId element_id,
+                                        ElementListType list_type,
+                                        AnimationChangeType change_type,
+                                        bool is_animating) override;
   void ScrollOffsetAnimationFinished() override;
   gfx::ScrollOffset GetScrollOffsetForAnimation(
       ElementId element_id) const override;
 
   virtual bool PrepareTiles();
 
   // Returns DRAW_SUCCESS unless problems occured preparing the frame, and we
   // should try to avoid displaying the frame. If PrepareToDraw is called,
   // DidDrawAllLayers must also be called, regardless of whether DrawLayers is
   // called between the two.
@@ skipping 550 matching lines @@
   std::unique_ptr<Viewport> viewport_;
 
   LayerTreeMutator* mutator_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_