Fixes crash introduced @ 153047 (you can hit crash by maximizing a

ash/wm/window_animations.h

Index: ash/wm/window_animations.h
diff --git a/ash/wm/window_animations.h b/ash/wm/window_animations.h
index 0705143192b67b94f3b7ebabcb7d73a41dc068c6..9ddeaca98659b0ada3b1513aeb877c074f051fc2 100644
--- a/ash/wm/window_animations.h
+++ b/ash/wm/window_animations.h
@@ -90,10 +90,6 @@ ASH_EXPORT base::TimeDelta GetCrossFadeDuration(const gfx::Rect& old_bounds,
 ASH_EXPORT bool AnimateOnChildWindowVisibilityChanged(
     aura::Window* window, bool visible);
 
-// Delay the old layer deletion so that test can verify the behavior of
-// old layer.
-ASH_EXPORT void SetDelayedOldLayerDeletionInCrossFadeForTest(bool value);
-
 }  // namespace internal
 }  // namespace ash