CC Animation: Use std::bitset to update animation state.

cc/animation/animation_player.h

Index: cc/animation/animation_player.h
diff --git a/cc/animation/animation_player.h b/cc/animation/animation_player.h
index 491f6fdf5cb88b915f93dc90e59246fb3c209809..43ee17505b206bd8ea8f2cade781aa84f1c1cf5c 100644
--- a/cc/animation/animation_player.h
+++ b/cc/animation/animation_player.h
@@ -5,7 +5,6 @@
 #ifndef CC_ANIMATION_ANIMATION_PLAYER_H_
 #define CC_ANIMATION_ANIMATION_PLAYER_H_
 
-#include <bitset>
 #include <vector>
 
 #include "base/macros.h"
@@ -107,10 +106,8 @@ class CC_EXPORT AnimationPlayer : public base::RefCounted<AnimationPlayer> {
 
   // Make animations affect active elements if and only if they affect
   // pending elements. Any animations that no longer affect any elements
-  // are deleted.
-  void ActivateAnimations(bool* changed_transform_animation,
-                          bool* changed_opacity_animation,
-                          bool* changed_filter_animation);
+  // are deleted. Returns a set of properties with animations activated.
+  TargetProperties ActivateAnimations();
 
   bool HasFilterAnimationThatInflatesBounds() const;
   bool HasTransformAnimationThatInflatesBounds() const;
@@ -152,8 +149,8 @@ class CC_EXPORT AnimationPlayer : public base::RefCounted<AnimationPlayer> {
   // Returns the active animation for the given unique animation id.
   Animation* GetAnimationById(int animation_id) const;
 
-  void GetPropertyAnimationStateFor(TargetProperty::Type property,
-                                    PropertyAnimationState* state) const;
+  void GetPropertyAnimationState(PropertyAnimationState* pending_state,
+                                 PropertyAnimationState* active_state) const;
 
  private:
   friend class base::RefCounted<AnimationPlayer>;
@@ -161,10 +158,6 @@ class CC_EXPORT AnimationPlayer : public base::RefCounted<AnimationPlayer> {
   explicit AnimationPlayer(int id);
   ~AnimationPlayer();
 
-  // A set of target properties. TargetProperty must be 0-based enum.
-  using TargetProperties =
-      std::bitset<TargetProperty::LAST_TARGET_PROPERTY + 1>;
-
   void SetNeedsCommit();
 
   void RegisterPlayer();