mash: Have chrome set itself as a controller interface for changing volume

chrome/browser/ui/ash/volume_controller_chromeos.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 CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_
-#define CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_
-
-#include "ash/public/interfaces/volume.mojom.h"
-#include "base/macros.h"
-#include "mojo/public/cpp/bindings/binding_set.h"
-
-// Controls the volume when F8-10 or a multimedia key for volume is pressed.
-class VolumeController : public ash::mojom::VolumeController {
- public:
-  VolumeController();
-  ~VolumeController() override;
-
-  // Binds the mojom::VolumeController interface request to this object.
-  void BindRequest(ash::mojom::VolumeControllerRequest request);
-
-  // Overridden from ash::mojom::VolumeController:
-  void VolumeMute() override;
-  void VolumeDown() override;
-  void VolumeUp() override;
-
- private:
-  mojo::BindingSet<ash::mojom::VolumeController> bindings_;
-
-  DISALLOW_COPY_AND_ASSIGN(VolumeController);
-};
-
-#endif  // CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_