Blink Compositor Animation: Introduce CompositorAnimationHost correctly.

third_party/WebKit/Source/platform/animation/CompositorAnimationTimeline.h

 // Copyright 2016 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 CompositorAnimationTimeline_h
 #define CompositorAnimationTimeline_h
 
 #include "base/memory/ref_counted.h"
 #include "cc/animation/animation_timeline.h"
 #include "platform/PlatformExport.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/PtrUtil.h"
 #include <memory>
 
 namespace blink {
 
-class CompositorAnimationHost;
 class CompositorAnimationPlayerClient;
 
 // A compositor representation for cc::AnimationTimeline.
 class PLATFORM_EXPORT CompositorAnimationTimeline {
   WTF_MAKE_NONCOPYABLE(CompositorAnimationTimeline);
 
  public:
   static std::unique_ptr<CompositorAnimationTimeline> create() {
     return WTF::wrapUnique(new CompositorAnimationTimeline());
   }
 
   ~CompositorAnimationTimeline();
 
   cc::AnimationTimeline* animationTimeline() const;
-  // TODO(ymalik): Currently we just wrap cc::AnimationHost in
-  // CompositorAnimationHost. Correctly introduce CompositorAnimationHost
-  // to blink. See crbug.com/610763.
-  CompositorAnimationHost compositorAnimationHost();
 
   void playerAttached(const CompositorAnimationPlayerClient&);
   void playerDestroyed(const CompositorAnimationPlayerClient&);
 
  private:
   CompositorAnimationTimeline();
 
   scoped_refptr<cc::AnimationTimeline> m_animationTimeline;
 };
 
 }  // namespace blink
 
 #endif  // CompositorAnimationTimeline_h