make menus, bubbles, etc. top level windows on aura

ui/aura/client/animation_host.h

Index: ui/aura/client/animation_host.h
diff --git a/ui/aura/client/animation_host.h b/ui/aura/client/animation_host.h
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index 0000000000000000000000000000000000000000..549c3469a8b803fd079cd5726500b5e19a3ccbf4
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+++ b/ui/aura/client/animation_host.h
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+// Copyright 2013 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_AURA_CLIENT_ANIMATION_HOST_H_
+#define UI_AURA_CLIENT_ANIMATION_HOST_H_
+
+#include "base/compiler_specific.h"
+#include "ui/aura/aura_export.h"
+
+namespace gfx {
+class Rect;
+}
+
+namespace aura {
+class Window;
+namespace client {
+
+// Interface for top level window host of animation. Communicates additional
+// bounds required for animation as well as animation completion for deferring
+// window closes on hide.
+class AURA_EXPORT AnimationHost {
+ public:
+  // Ensure the host window is at least this large so that transitions have
+  // sufficient space.
+  virtual void SetHostTransitionBounds(const gfx::Rect& bounds) = 0;
+
+  // Called after the window has faded out on a hide.
+  virtual void OnWindowHidingAnimationCompleted() = 0;
+
+ protected:
+  virtual ~AnimationHost() {}
+};
+
+AURA_EXPORT void SetAnimationHost(Window* window,
+                                  AnimationHost* animation_host);
+AURA_EXPORT AnimationHost* GetAnimationHost(Window* window);
+
+}  // namespace client
+}  // namespace aura
+
+#endif  // UI_AURA_CLIENT_ANIMATION_HOST_H_