NOT READY FOR REVIEW - Add support for custom animation timers.

ui/compositor/layer_animator.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_ANIMATOR_H_
 #define UI_COMPOSITOR_LAYER_ANIMATOR_H_
 
 #include <deque>
 #include <vector>
 
@@ skipping 11 matching lines @@
 class Rect;
 class Transform;
 }
 
 namespace ui {
 class Animation;
 class Layer;
 class LayerAnimationSequence;
 class LayerAnimationDelegate;
 class LayerAnimationObserver;
+class LayerAnimationTimer;
 class ScopedLayerAnimationSettings;
 
 // When a property of layer needs to be changed it is set by way of
 // LayerAnimator. This enables LayerAnimator to animate property changes.
 // NB: during many tests, set_disable_animations_for_test is used and causes
 // all animations to complete immediately. The layer animation is ref counted
 // so that if its owning layer is deleted (and the owning layer is only other
 // class that should ever hold a ref ptr to a LayerAnimator), the animator can
 // ensure that it is not disposed of until it finishes executing. It does this
 // by holding a reference to itself for the duration of methods for which it
@@ skipping 144 matching lines @@
 
   // When set to true, all animations complete immediately.
   static void set_disable_animations_for_test(bool disable_animations) {
     disable_animations_for_test_ = disable_animations;
   }
 
   static bool disable_animations_for_test() {
     return disable_animations_for_test_;
   }
 
+  // Takes ownership of the given timer.
+  // FIXME(vollick): Once we've written a TestLayerAnimationTimer than can be
+  // used to advance animations, we can probably get rid of last_tick_time() and
+  // all the code in the layer animation tests that advances animations using
+  // AnimationContainerElement::Step.
+  static void SetAnimationTimer(LayerAnimationTimer* timer);
+
  protected:
   virtual ~LayerAnimator();
 
   LayerAnimationDelegate* delegate() { return delegate_; }
   const LayerAnimationDelegate* delegate() const { return delegate_; }
 
   // Virtual for testing.
   virtual void ProgressAnimation(LayerAnimationSequence* sequence,
                                  base::TimeDelta delta);
 
@@ skipping 150 matching lines @@
   // Observers are notified when layer animations end, are scheduled or are
   // aborted.
   ObserverList<LayerAnimationObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerAnimator);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_LAYER_ANIMATOR_H_