Thread ui transform animations

ui/compositor/layer_animation_element.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_COMPOSITOR_LAYER_ANIMATION_ELEMENT_H_
 #define UI_COMPOSITOR_LAYER_ANIMATION_ELEMENT_H_
 
 #include <set>
 
 #include "base/time.h"
@@ skipping 174 matching lines @@
  protected:
   // Called once each time the animation element is run before any call to
   // OnProgress.
   virtual void OnStart(LayerAnimationDelegate* delegate) = 0;
   virtual bool OnProgress(double t, LayerAnimationDelegate* delegate) = 0;
   virtual void OnGetTarget(TargetValue* target) const = 0;
   virtual void OnAbort(LayerAnimationDelegate* delegate) = 0;
 
   base::TimeDelta duration() const { return duration_; }
 
+  base::TimeDelta duration() { return duration_; }
+
   // Actually start the animation, dispatching to another thread if needed.
   virtual void RequestEffectiveStart(LayerAnimationDelegate* delegate);
 
  private:
   // For debugging purposes, we sometimes alter the duration we actually use.
   // For example, during tests we often set duration = 0, and it is sometimes
   // useful to slow animations down to see them more clearly.
   base::TimeDelta GetEffectiveDuration(const base::TimeDelta& delta);
 
   bool first_frame_;
   const AnimatableProperties properties_;
   base::TimeTicks requested_start_time_;
 
   // When the animation actually started, taking into account queueing delays.
   base::TimeTicks effective_start_time_;
   const base::TimeDelta duration_;
   Tween::Type tween_type_;
 
   const int animation_id_;
   int animation_group_id_;
 
   double last_progressed_fraction_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerAnimationElement);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_LAYER_ANIMATION_ELEMENT_H_