Improved AGC update scheme for the audio backend in Chrome

media/audio/mac/audio_low_latency_input_mac.h

Index: media/audio/mac/audio_low_latency_input_mac.h
diff --git a/media/audio/mac/audio_low_latency_input_mac.h b/media/audio/mac/audio_low_latency_input_mac.h
index 04a4ff81373ce1bed4b56bd2d0048dba3f8fdcc6..07a727bd8db230be9a533eb39fdf9ee2291a33d0 100644
--- a/media/audio/mac/audio_low_latency_input_mac.h
+++ b/media/audio/mac/audio_low_latency_input_mac.h
@@ -42,8 +42,8 @@
 #include "base/atomicops.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
+#include "media/audio/agc_audio_stream.h"
 #include "media/audio/audio_io.h"
-#include "media/audio/audio_input_stream_impl.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/seekable_buffer.h"
 
@@ -52,7 +52,7 @@ namespace media {
 class AudioManagerMac;
 class DataBuffer;
 
-class AUAudioInputStream : public AudioInputStreamImpl {
+class AUAudioInputStream : public AgcAudioStream<AudioInputStream> {
  public:
   // The ctor takes all the usual parameters, plus |manager| which is the
   // the audio manager who is creating this object.