Added a nested class to gfx::Animation

ui/gfx/animation/animation.h

 // 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 UI_GFX_ANIMATION_ANIMATION_H_
 #define UI_GFX_ANIMATION_ANIMATION_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "ui/gfx/animation/animation_container_element.h"
 
 namespace gfx {
 class Rect;
 }
 
 namespace gfx {
 
 class AnimationContainer;
 class AnimationDelegate;
+class AnimationTestApi;
 
 // Base class used in implementing animations. You only need use this class if
 // you're implementing a new animation type, otherwise you'll likely want one of
 // LinearAnimation, SlideAnimation, ThrobAnimation or MultiAnimation.
 //
 // To subclass override Step, which is invoked as the animation progresses and
 // GetCurrentValue() to return the value appropriate to the animation.
 class ANIMATION_EXPORT Animation : public AnimationContainerElement {
  public:
   explicit Animation(base::TimeDelta timer_interval);
@@ skipping 53 matching lines @@
   AnimationContainer* container() { return container_.get(); }
   base::TimeTicks start_time() const { return start_time_; }
   AnimationDelegate* delegate() { return delegate_; }
 
   // AnimationContainer::Element overrides
   void SetStartTime(base::TimeTicks start_time) override;
   void Step(base::TimeTicks time_now) override = 0;
   base::TimeDelta GetTimerInterval() const override;
 
  private:
+  friend class AnimationTestApi;
+
   // Interval for the animation.
   const base::TimeDelta timer_interval_;
 
   // If true we're running.
   bool is_animating_;
 
   // Our delegate; may be null.
   AnimationDelegate* delegate_;
 
   // Container we're in. If non-null we're animating.
   scoped_refptr<AnimationContainer> container_;
 
   // Time we started at.
   base::TimeTicks start_time_;
 
   DISALLOW_COPY_AND_ASSIGN(Animation);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_ANIMATION_ANIMATION_H_