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

media/audio/audio_io.h

Index: media/audio/audio_io.h
diff --git a/media/audio/audio_io.h b/media/audio/audio_io.h
index f6151e094e13afac29bde85e82b6b2ad7b19dc43..1e1eba420b14aa049bacbf91a9841ec452e1c6ed 100644
--- a/media/audio/audio_io.h
+++ b/media/audio/audio_io.h
@@ -109,9 +109,18 @@ class MEDIA_EXPORT AudioInputStream {
     // Called by the audio recorder when a full packet of audio data is
     // available. This is called from a special audio thread and the
     // implementation should return as soon as possible.
-    virtual void OnData(AudioInputStream* stream, const uint8* src,
-                        uint32 size, uint32 hardware_delay_bytes,
-                        double volume) = 0;
+    // TODO(henrika): should be pure virtual when old OnData() is phased out.
+    virtual void OnData(AudioInputStream* stream,
+                        const AudioBus* source,
+                        uint32 hardware_delay_bytes,
+                        double volume) {};
+
+    // TODO(henrika): don't use; to be removed.
+    virtual void OnData(AudioInputStream* stream,
+                        const uint8* src,
+                        uint32 size,
+                        uint32 hardware_delay_bytes,
+                        double volume) {};
 
     // There was an error while recording audio. The audio sink cannot be
     // destroyed yet. No direct action needed by the AudioInputStream, but it