Remove WebRtc audio source references for local audio tracks.

content/renderer/media/webrtc/processed_local_audio_source.h

Index: content/renderer/media/webrtc/processed_local_audio_source.h
diff --git a/content/renderer/media/webrtc/processed_local_audio_source.h b/content/renderer/media/webrtc/processed_local_audio_source.h
index 3cbfe40371ee44e9654b59d602509b29bd14b325..5d2e38862bdf74547a7049065a462968e4415cae 100644
--- a/content/renderer/media/webrtc/processed_local_audio_source.h
+++ b/content/renderer/media/webrtc/processed_local_audio_source.h
@@ -66,7 +66,6 @@ class CONTENT_EXPORT ProcessedLocalAudioSource final
 
   // The following accessors are not valid until after the source is started
   // (when the first track is connected).
-  webrtc::AudioSourceInterface* rtc_source() const { return rtc_source_.get(); }
   const scoped_refptr<MediaStreamAudioProcessor>& audio_processor() const {
     return audio_processor_;
   }
@@ -127,10 +126,6 @@ class CONTENT_EXPORT ProcessedLocalAudioSource final
   // Lock used to ensure thread-safe access to |source_| by SetVolume().
   mutable base::Lock source_lock_;
 
-  // Holder for WebRTC audio pipeline objects. Created in
-  // EnsureSourceIsStarted().
-  scoped_refptr<webrtc::AudioSourceInterface> rtc_source_;
-
   // Stores latest microphone volume received in a CaptureData() callback.
   // Range is [0, 255].
   base::subtle::Atomic32 volume_;