ash: Improved window maximize/restore animations

ui/compositor/layer_animator.h

Index: ui/compositor/layer_animator.h
diff --git a/ui/compositor/layer_animator.h b/ui/compositor/layer_animator.h
index 4f41bb531cca222e3b050e782cc519e7114f6247..a522946d1c5fe6970e20843861713746aac2847c 100644
--- a/ui/compositor/layer_animator.h
+++ b/ui/compositor/layer_animator.h
@@ -144,6 +144,11 @@ class COMPOSITOR_EXPORT LayerAnimator : public AnimationContainerElement {
     return disable_animations_for_test_;
   }
 
+  // Set |time_scale| > 1 to slow down animations for visual testing.
+  static void set_time_scale_for_test(int time_scale) {
+    time_scale_for_test_ = time_scale;
+  }
+
  protected:
   LayerAnimationDelegate* delegate() { return delegate_; }
   const LayerAnimationDelegate* delegate() const { return delegate_; }
@@ -271,6 +276,9 @@ class COMPOSITOR_EXPORT LayerAnimator : public AnimationContainerElement {
   // This causes all animations to complete immediately.
   static bool disable_animations_for_test_;
 
+  // Scales all animation durations by this factor.
+  static int time_scale_for_test_;
+
   // Observers are notified when layer animations end, are scheduled or are
   // aborted.
   ObserverList<LayerAnimationObserver> observers_;