Move media/audio files into media namespace

media/audio/linux/alsa_wrapper.h

Index: media/audio/linux/alsa_wrapper.h
diff --git a/media/audio/linux/alsa_wrapper.h b/media/audio/linux/alsa_wrapper.h
index 49d64b232d4dd8824746464fa03e81dbad420a1f..30d94635dd5cdd6c636b9a065d465f6948d20e81 100644
--- a/media/audio/linux/alsa_wrapper.h
+++ b/media/audio/linux/alsa_wrapper.h
@@ -11,6 +11,8 @@
 #include "base/basictypes.h"
 #include "media/base/media_export.h"
 
+namespace media {
+
 class MEDIA_EXPORT AlsaWrapper {
  public:
   AlsaWrapper();
@@ -75,3 +77,5 @@ class MEDIA_EXPORT AlsaWrapper {
                         int soft_resample, unsigned int latency);
   DISALLOW_COPY_AND_ASSIGN(AlsaWrapper);
 };
+
+}  // namespace media