chromeos: Combine TrayAudio and TrayAudioChromeOs classes

ash/common/system/chromeos/audio/tray_audio_delegate.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_COMMON_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_H_
-#define ASH_COMMON_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_H_
+#ifndef ASH_COMMON_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_DELEGATE_H_
+#define ASH_COMMON_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_DELEGATE_H_
 
 namespace gfx {
 struct VectorIcon;
 }
 
 namespace ash {
 namespace system {
 
-class ASH_EXPORT TrayAudioDelegate {
+class TrayAudioDelegate {
  public:
   enum { kNoAudioDeviceIcon = -1 };
   enum AudioChannelMode {
     NORMAL,
     LEFT_RIGHT_SWAPPED,
   };
 
   virtual ~TrayAudioDelegate() {}
 
   // Sets the volume level of the output device to the minimum level which is
@@ skipping 36 matching lines @@
   // |force_rediscovering| is true, it will force to set the starting point for
   // re-discovering the active HDMI output device again if it has been in the
   // middle of rediscovering the HDMI active output device.
   virtual void SetActiveHDMIOutoutRediscoveringIfNecessary(
       bool force_rediscovering) = 0;
 };
 
 }  // namespace system
 }  // namespace ash
 
-#endif  // ASH_COMMON_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_H_
+#endif  // ASH_COMMON_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_DELEGATE_H_