It is time.

ui/wm/core/transient_window_controller.h

-// Copyright 2014 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_WM_CORE_TRANSIENT_WINDOW_CONTROLLER_H_
-#define UI_WM_CORE_TRANSIENT_WINDOW_CONTROLLER_H_
-
-#include "ui/wm/public/transient_window_client.h"
-#include "ui/wm/wm_export.h"
-
-namespace wm {
-
-// TransientWindowClient implementation. Uses TransientWindowManager to handle
-// tracking transient per window.
-class WM_EXPORT TransientWindowController
-    : public aura::client::TransientWindowClient {
- public:
-  TransientWindowController();
-  virtual ~TransientWindowController();
-
-  // TransientWindowClient:
-  virtual void AddTransientChild(aura::Window* parent,
-                                 aura::Window* child) override;
-  virtual void RemoveTransientChild(aura::Window* parent,
-                                    aura::Window* child) override;
-  virtual aura::Window* GetTransientParent(aura::Window* window) override;
-  virtual const aura::Window* GetTransientParent(
-      const aura::Window* window) override;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(TransientWindowController);
-};
-
-}  // namespace wm
-
-#endif  // UI_WM_CORE_TRANSIENT_WINDOW_CONTROLLER_H_