Modifies AudioInputCallback::OnData and use media::AudioBus instead of plain byte vector (Relanding)

media/audio/cras/cras_input.h

Index: media/audio/cras/cras_input.h
diff --git a/media/audio/cras/cras_input.h b/media/audio/cras/cras_input.h
index 36bf9b140fc1f49a7cafb83a6a251ba4e78acec4..1919224d9a9b2f77187c35a1f0a669f5aef2d629 100644
--- a/media/audio/cras/cras_input.h
+++ b/media/audio/cras/cras_input.h
@@ -98,6 +98,8 @@ class CrasInputStream : public AgcAudioStream<AudioInputStream> {
   // Direction of the stream.
   const CRAS_STREAM_DIRECTION stream_direction_;
 
+  scoped_ptr<AudioBus> audio_bus_;
+
   DISALLOW_COPY_AND_ASSIGN(CrasInputStream);
 };