Thread ui opacity animations

ui/compositor/layer_animation_sequence.h

Index: ui/compositor/layer_animation_sequence.h
diff --git a/ui/compositor/layer_animation_sequence.h b/ui/compositor/layer_animation_sequence.h
index 9691ee783a71f7cd7ec12494e8add8eeddb3e218..9c8514250d6a601545909083d49129a3290f9c1f 100644
--- a/ui/compositor/layer_animation_sequence.h
+++ b/ui/compositor/layer_animation_sequence.h
@@ -47,6 +47,18 @@ class COMPOSITOR_EXPORT LayerAnimationSequence
   void set_start_time(base::TimeTicks start_time) { start_time_ = start_time; }
   base::TimeTicks start_time() const { return start_time_; }
 
+  // Sets a flag indicating that this sequence will start together with other
+  // sequences, and at least one of the sequences in this group has a threaded
+  // first element.
+  void set_waiting_for_group_start(bool waiting) {
+    waiting_for_group_start_ = waiting;
+  }
+  bool waiting_for_group_start() { return waiting_for_group_start_; }
+
+  // If starting the animation involves dispatching to another thread, then
+  // proceed with that dispatch.
+  void ProgressToEffectiveStart(LayerAnimationDelegate* delegate);
+
   // Updates the delegate to the appropriate value for |now|. Requests a
   // redraw if it is required.
   void Progress(base::TimeTicks now, LayerAnimationDelegate* delegate);
@@ -64,7 +76,7 @@ class COMPOSITOR_EXPORT LayerAnimationSequence
   void GetTargetValue(LayerAnimationElement::TargetValue* target) const;
 
   // Aborts the given animation.
-  void Abort();
+  void Abort(LayerAnimationDelegate* delegate);
 
   // All properties modified by the sequence.
   const LayerAnimationElement::AnimatableProperties& properties() const {
@@ -84,11 +96,21 @@ class COMPOSITOR_EXPORT LayerAnimationSequence
   bool HasCommonProperty(
       const LayerAnimationElement::AnimatableProperties& other) const;
 
+  // Returns true if the first element animates on the compositor thread.
+  bool IsFirstElementThreaded() const;
+
+  // Used to identify groups of sequences that are supposed to start together.
+  int animation_group_id() const { return animation_group_id_; }
+  void set_animation_group_id(int id) { animation_group_id_ = id; }
+
   // These functions are used for adding or removing observers from the observer
   // list. The observers are notified when animations end.
   void AddObserver(LayerAnimationObserver* observer);
   void RemoveObserver(LayerAnimationObserver* observer);
 
+  // Called when a threaded animation is actually started.
+  void OnThreadedAnimationStarted(const cc::AnimationEvent& event);
+
   // Called when the animator schedules this sequence.
   void OnScheduled();
 
@@ -126,6 +148,13 @@ class COMPOSITOR_EXPORT LayerAnimationSequence
   // The start time of the current run of the sequence.
   base::TimeTicks start_time_;
 
+  // True if this sequence will start together with other sequences, and at
+  // least one of the sequences in this group has a threaded first element.
+  bool waiting_for_group_start_;
+
+  // Identifies groups of sequences that are supposed to start together.
+  int animation_group_id_;
+
   // These parties are notified when layer animations end.
   ObserverList<LayerAnimationObserver> observers_;