Move media/audio files into media namespace

media/audio/win/audio_manager_win.h

Index: media/audio/win/audio_manager_win.h
diff --git a/media/audio/win/audio_manager_win.h b/media/audio/win/audio_manager_win.h
index 19742fb6d49950effbea96af8bc9f8eec640b792..b1e242657c3e7e2ad7dababe1f57daeff38b9afa 100644
--- a/media/audio/win/audio_manager_win.h
+++ b/media/audio/win/audio_manager_win.h
@@ -13,6 +13,8 @@
 #include "base/gtest_prod_util.h"
 #include "media/audio/audio_manager_base.h"
 
+namespace media {
+
 // Windows implementation of the AudioManager singleton. This class is internal
 // to the audio output and only internal users can call methods not exposed by
 // the AudioManager class.
@@ -71,4 +73,6 @@ class MEDIA_EXPORT AudioManagerWin : public AudioManagerBase {
   DISALLOW_COPY_AND_ASSIGN(AudioManagerWin);
 };
 
+}  // namespace media
+
 #endif  // MEDIA_AUDIO_WIN_AUDIO_MANAGER_WIN_H_