Move media/audio files into media namespace (relanding)

media/audio/mac/audio_output_mac.h

Index: media/audio/mac/audio_output_mac.h
diff --git a/media/audio/mac/audio_output_mac.h b/media/audio/mac/audio_output_mac.h
index e033fc96abfa5d72598fbbae70edb18ff38fe47d..66f2941ae896cc3b0534843b3295369b76f9aea6 100644
--- a/media/audio/mac/audio_output_mac.h
+++ b/media/audio/mac/audio_output_mac.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -14,6 +14,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerMac;
 
 // Implementation of AudioOuputStream for Mac OS X using the audio queue service
@@ -97,4 +99,6 @@ class PCMQueueOutAudioOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(PCMQueueOutAudioOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_MAC_AUDIO_OUTPUT_MAC_H_