Upgrade AudioBus to support wrapping, interleaving.

media/base/audio_renderer_mixer.cc

Index: media/base/audio_renderer_mixer.cc
diff --git a/media/base/audio_renderer_mixer.cc b/media/base/audio_renderer_mixer.cc
index 503f139fdc52f1fd1179db5972e6ae799922c27e..b9ec259a11662a84a5142e0b7f9bb4a7a0ba23a0 100644
--- a/media/base/audio_renderer_mixer.cc
+++ b/media/base/audio_renderer_mixer.cc
@@ -120,9 +120,6 @@ void AudioRendererMixer::ProvideInput(AudioBus* audio_bus) {
        VectorFMAC(mixer_input_audio_bus_->channel(i), volume, frames_filled,
                   audio_bus->channel(i));
     }
-
-    // No need to clamp values as InterleaveFloatToInt() will take care of this
-    // for us later when data is transferred to the browser process.
   }
 }