Thread ui opacity animations

ui/compositor/layer_animation_delegate.h

Index: ui/compositor/layer_animation_delegate.h
diff --git a/ui/compositor/layer_animation_delegate.h b/ui/compositor/layer_animation_delegate.h
index 223eca2a781b3fe2222ee60721c4824f5349ba24..765c2d05a1a8a82ba274e56e84b50af5281e123c 100644
--- a/ui/compositor/layer_animation_delegate.h
+++ b/ui/compositor/layer_animation_delegate.h
@@ -5,11 +5,16 @@
 #ifndef UI_COMPOSITOR_LAYER_ANIMATION_DELEGATE_H_
 #define UI_COMPOSITOR_LAYER_ANIMATION_DELEGATE_H_
 
+#include "base/memory/scoped_ptr.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/compositor/compositor_export.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/transform.h"
 
+namespace cc {
+class Animation;
+}
+
 namespace ui {
 
 // Layer animations interact with the layers using this interface.
@@ -30,6 +35,8 @@ class COMPOSITOR_EXPORT LayerAnimationDelegate {
   virtual float GetBrightnessForAnimation() const = 0;
   virtual float GetGrayscaleForAnimation() const = 0;
   virtual SkColor GetColorForAnimation() const = 0;
+  virtual void AddThreadedAnimation(scoped_ptr<cc::Animation> animation) = 0;
+  virtual void RemoveThreadedAnimation(int animation_id) = 0;
 
  protected:
   virtual ~LayerAnimationDelegate() {}