Reland: mash: Convert TrayBackgroundView to wm common types

ash/system/tray/tray_bubble_wrapper.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 ASH_SYSTEM_TRAY_TRAY_BUBBLE_WRAPPER_H_
-#define ASH_SYSTEM_TRAY_TRAY_BUBBLE_WRAPPER_H_
-
-#include "base/macros.h"
-#include "ui/views/widget/widget_observer.h"
-
-namespace views {
-class TrayBubbleView;
-}
-
-namespace ash {
-class TrayBackgroundView;
-class TrayEventFilter;
-
-// Creates and manages the Widget and EventFilter components of a bubble.
-
-class TrayBubbleWrapper : public views::WidgetObserver {
- public:
-  TrayBubbleWrapper(TrayBackgroundView* tray,
-                    views::TrayBubbleView* bubble_view);
-  ~TrayBubbleWrapper() override;
-
-  // views::WidgetObserver overrides:
-  void OnWidgetDestroying(views::Widget* widget) override;
-  void OnWidgetBoundsChanged(views::Widget* widget,
-                             const gfx::Rect& new_bounds) override;
-
-  const TrayBackgroundView* tray() const { return tray_; }
-  TrayBackgroundView* tray() { return tray_; }
-  const views::TrayBubbleView* bubble_view() const { return bubble_view_; }
-  const views::Widget* bubble_widget() const { return bubble_widget_; }
-
- private:
-  TrayBackgroundView* tray_;
-  views::TrayBubbleView* bubble_view_;  // unowned
-  views::Widget* bubble_widget_;
-
-  DISALLOW_COPY_AND_ASSIGN(TrayBubbleWrapper);
-};
-
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_TRAY_TRAY_BUBBLE_WRAPPER_H_