Move media/audio files into media namespace (relanding)

media/audio/android/audio_track_output_android.h

Index: media/audio/android/audio_track_output_android.h
diff --git a/media/audio/android/audio_track_output_android.h b/media/audio/android/audio_track_output_android.h
index ddeab43d553a2a99399ffa649399785ff37927b2..0ab76471f77cf7cb9f79e947b9c15eb6f7deb51f 100644
--- a/media/audio/android/audio_track_output_android.h
+++ b/media/audio/android/audio_track_output_android.h
@@ -14,6 +14,8 @@
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 
+namespace media {
+
 class AudioManagerAndroid;
 
 // Implements PCM audio output support for Android using the AudioTrack API.
@@ -68,4 +70,6 @@ class AudioTrackOutputStream : public AudioOutputStream {
   DISALLOW_COPY_AND_ASSIGN(AudioTrackOutputStream);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_ANDROID_AUDIO_TRACK_OUTPUT_ANDROID_H_