Move ash tray audio UI code from ash/system/audio to ash/system/chromeos/audio.

ash/system/audio/tray_volume.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_AUDIO_TRAY_VOLUME_H_
-#define ASH_SYSTEM_AUDIO_TRAY_VOLUME_H_
-
-#include "ash/system/audio/audio_observer.h"
-#include "ash/system/tray/tray_image_item.h"
-
-namespace ash {
-namespace internal {
-
-namespace tray {
-class VolumeView;
-}
-
-class TrayVolume : public TrayImageItem,
-                   public AudioObserver {
- public:
-  explicit TrayVolume(SystemTray* system_tray);
-  virtual ~TrayVolume();
-
- private:
-  // Overridden from TrayImageItem.
-  virtual bool GetInitialVisibility() OVERRIDE;
-
-  // Overridden from SystemTrayItem.
-  virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE;
-  virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE;
-  virtual void DestroyDefaultView() OVERRIDE;
-  virtual void DestroyDetailedView() OVERRIDE;
-  virtual bool ShouldHideArrow() const OVERRIDE;
-  virtual bool ShouldShowLauncher() const OVERRIDE;
-
-  // Overridden from AudioObserver.
-  virtual void OnVolumeChanged(float percent) OVERRIDE;
-  virtual void OnMuteToggled() OVERRIDE;
-
-  tray::VolumeView* volume_view_;
-
-  // Was |volume_view_| created for CreateDefaultView() rather than
-  // CreateDetailedView()?  Used to avoid resetting |volume_view_|
-  // inappropriately in DestroyDefaultView() or DestroyDetailedView().
-  bool is_default_view_;
-
-  DISALLOW_COPY_AND_ASSIGN(TrayVolume);
-};
-
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_AUDIO_TRAY_VOLUME_H_