Revert of Enable the volume slider in Ash for windows.

ash/system/win/audio/tray_audio_delegate_win.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 ASH_SYSTEM_WIN_AUDIO_TRAY_AUDIO_DELEGATE_WIN_H_
-#define ASH_SYSTEM_WIN_AUDIO_TRAY_AUDIO_DELEGATE_WIN_H_
-
-#include <audioclient.h>
-#include <mmdeviceapi.h>
-
-#include "ash/ash_export.h"
-#include "ash/system/audio/tray_audio_delegate.h"
-#include "base/compiler_specific.h"
-#include "base/win/scoped_comptr.h"
-
-namespace ash {
-namespace system {
-
-class ASH_EXPORT TrayAudioDelegateWin : public TrayAudioDelegate {
- public:
-  virtual ~TrayAudioDelegateWin() {}
-
-  // Overridden from TrayAudioDelegate.
-  virtual void AdjustOutputVolumeToAudibleLevel() OVERRIDE;
-  virtual int GetOutputDefaultVolumeMuteLevel() OVERRIDE;
-  virtual int GetOutputVolumeLevel() OVERRIDE;
-  virtual int GetActiveOutputDeviceIconId() OVERRIDE;
-  virtual bool HasAlternativeSources() OVERRIDE;
-  virtual bool IsOutputAudioMuted() OVERRIDE;
-  virtual void SetOutputAudioIsMuted(bool is_muted) OVERRIDE;
-  virtual void SetOutputVolumeLevel(int level) OVERRIDE;
-
- private:
-  base::win::ScopedComPtr<ISimpleAudioVolume> CreateDefaultVolumeControl();
-};
-
-}  // namespace system
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_WIN_AUDIO_TRAY_AUDIO_DELEGATE_WIN_H_