Fixed the racing in the resampler of webrtc when two streams are calling OnData()

content/renderer/media/webrtc_audio_device_impl.h

Index: content/renderer/media/webrtc_audio_device_impl.h
diff --git a/content/renderer/media/webrtc_audio_device_impl.h b/content/renderer/media/webrtc_audio_device_impl.h
index f515c6e24cbc2bcea6d2bcb7fb027e6cc39b23e0..1d904fa496202277130bc900edb0aea72b525472 100644
--- a/content/renderer/media/webrtc_audio_device_impl.h
+++ b/content/renderer/media/webrtc_audio_device_impl.h
@@ -385,6 +385,10 @@ class CONTENT_EXPORT WebRtcAudioDeviceImpl
   // |recording_| and |microphone_volume_|.
   mutable base::Lock lock_;
 
+  // Used to protect the racing of calling OnData() since there can be more
+  // than one input stream calling OnData().
+  mutable base::Lock capture_callback_lock_;
+
   bool initialized_;
   bool playing_;
   bool recording_;