Move animation code to new ui/base/animation directory....

app/animation_container_element.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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 APP_ANIMATION_CONTAINER_ELEMENT_H_
 #define APP_ANIMATION_CONTAINER_ELEMENT_H_
 #pragma once
 
-#include "base/time.h"
+#include "ui/base/animation/animation_container_element.h"
 
-// Interface for the elements the AnimationContainer contains. This is
-// implemented by Animation.
-class AnimationContainerElement {
- public:
-  // Sets the start of the animation. This is invoked from
-  // AnimationContainer::Start.
-  virtual void SetStartTime(base::TimeTicks start_time) = 0;
-
-  // Invoked when the animation is to progress.
-  virtual void Step(base::TimeTicks time_now) = 0;
-
-  // Returns the time interval of the animation. If an Element needs to change
-  // this it should first invoke Stop, then Start.
-  virtual base::TimeDelta GetTimerInterval() const = 0;
-
- protected:
-  virtual ~AnimationContainerElement() {}
-};
+using ui::AnimationContainerElement;
 
 #endif  // APP_ANIMATION_CONTAINER_ELEMENT_H_