CC Animation: Expose TargetProperty enum to be aliased in Blink Platform.

cc/animation/layer_animation_controller.h

Index: cc/animation/layer_animation_controller.h
diff --git a/cc/animation/layer_animation_controller.h b/cc/animation/layer_animation_controller.h
index 70c76d104c51241fdc7af58ddd7a0d3b7d1935f9..d7296a90cf76db45e862490f6c7de049b28084d5 100644
--- a/cc/animation/layer_animation_controller.h
+++ b/cc/animation/layer_animation_controller.h
@@ -47,7 +47,7 @@ class CC_EXPORT LayerAnimationController
   void PauseAnimation(int animation_id, base::TimeDelta time_offset);
   void RemoveAnimation(int animation_id);
   void AbortAnimation(int animation_id);
-  void AbortAnimations(Animation::TargetProperty target_property);
+  void AbortAnimations(AnimationTargetProperty target_property);
 
   // Ensures that the list of active animations on the main thread and the impl
   // thread are kept in sync. This function does not take ownership of the impl
@@ -68,7 +68,7 @@ class CC_EXPORT LayerAnimationController
 
   // Returns the active animation animating the given property that is either
   // running, or is next to run, if such an animation exists.
-  Animation* GetAnimation(Animation::TargetProperty target_property) const;
+  Animation* GetAnimation(AnimationTargetProperty target_property) const;
 
   // Returns the active animation for the given unique animation id.
   Animation* GetAnimationById(int animation_id) const;
@@ -83,12 +83,12 @@ class CC_EXPORT LayerAnimationController
   // Returns true if there is an animation that is either currently animating
   // the given property or scheduled to animate this property in the future, and
   // that affects the given observer type.
-  bool IsPotentiallyAnimatingProperty(Animation::TargetProperty target_property,
+  bool IsPotentiallyAnimatingProperty(AnimationTargetProperty target_property,
                                       ObserverType observer_type) const;
 
   // Returns true if there is an animation that is currently animating the given
   // property and that affects the given observer type.
-  bool IsCurrentlyAnimatingProperty(Animation::TargetProperty target_property,
+  bool IsCurrentlyAnimatingProperty(AnimationTargetProperty target_property,
                                     ObserverType observer_type) const;
 
   void SetAnimationRegistrar(AnimationRegistrar* registrar);
@@ -175,7 +175,7 @@ class CC_EXPORT LayerAnimationController
   virtual ~LayerAnimationController();
 
  private:
-  using TargetProperties = std::unordered_set<int>;
+  using TargetProperties = std::unordered_set<AnimationTargetProperty>;
 
   void PushNewAnimationsToImplThread(
       LayerAnimationController* controller_impl) const;