Compact layout mananger animates windows rather than the default container layer.

ui/gfx/compositor/scoped_layer_animation_settings.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_GFX_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_
 #define UI_GFX_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_
 #pragma once
 
 #include <set>
 
 #include "base/time.h"
 
 #include "ui/gfx/compositor/compositor_export.h"
+#include "ui/gfx/compositor/layer_animator.h"
 
 namespace ui {
 
 class ImplicitAnimationObserver;
-class LayerAnimator;
 class LayerAnimationObserver;
 
 // Scoped settings allow you to temporarily change the animator's settings and
 // these changes are reverted when the object is destroyed. NOTE: when the
 // settings object is created, it applies the default transition duration
 // (200ms).
 class COMPOSITOR_EXPORT ScopedLayerAnimationSettings {
  public:
   explicit ScopedLayerAnimationSettings(LayerAnimator* animator);
   virtual ~ScopedLayerAnimationSettings();
 
   void AddObserver(ImplicitAnimationObserver* observer);
   void SetTransitionDuration(base::TimeDelta duration);
+  void SetPreemptionStrategy(LayerAnimator::PreemptionStrategy strategy);
 
  private:
   LayerAnimator* animator_;
   base::TimeDelta old_transition_duration_;
+  LayerAnimator::PreemptionStrategy old_preemption_strategy_;
   std::set<ImplicitAnimationObserver*> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedLayerAnimationSettings);
 };
 
 }  // namespace ui
 
 #endif  // UI_GFX_COMPOSITOR_SCOPED_LAYER_ANIMATION_SETTINGS_H_