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

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index 02e64f4eb50f0181e2464729c238ab8b2993de2d..4f115c1c3aa50835ebe3c1175965e330aee0df7a 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -119,13 +119,13 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
 
   // AnimationDelegate implementation.
   void NotifyAnimationStarted(base::TimeTicks monotonic_time,
-                              Animation::TargetProperty target_property,
+                              AnimationTargetProperty::Enum target_property,
                               int group) override{};
   void NotifyAnimationFinished(base::TimeTicks monotonic_time,
-                               Animation::TargetProperty target_property,
+                               AnimationTargetProperty::Enum target_property,
                                int group) override;
   void NotifyAnimationAborted(base::TimeTicks monotonic_time,
-                              Animation::TargetProperty target_property,
+                              AnimationTargetProperty::Enum target_property,
                               int group) override{};
 
   // Tree structure.
@@ -555,7 +555,7 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   // This includes all animations, even those that are finished but haven't yet
   // been deleted.
   bool HasAnyAnimationTargetingProperty(
-      Animation::TargetProperty property) const;
+      AnimationTargetProperty::Enum property) const;
 
   bool HasFilterAnimationThatInflatesBounds() const;
   bool HasTransformAnimationThatInflatesBounds() const;