MediaStream audio: Refactor 3 separate "glue" implementations into one.

content/content_renderer.gypi

Index: content/content_renderer.gypi
diff --git a/content/content_renderer.gypi b/content/content_renderer.gypi
index 84fb9bb107108e3db082efe7a368f84c43f542bf..f7f402223b376b413888c6777f6333610a4282bb 100644
--- a/content/content_renderer.gypi
+++ b/content/content_renderer.gypi
@@ -315,10 +315,15 @@
       'renderer/media/cdm/ppapi_decryptor.h',
       'renderer/media/cdm/render_cdm_factory.cc',
       'renderer/media/cdm/render_cdm_factory.h',
+      'renderer/media/external_media_stream_audio_source.cc',
+      'renderer/media/external_media_stream_audio_source.h',
       'renderer/media/media_permission_dispatcher.cc',
       'renderer/media/media_permission_dispatcher.h',
+      'renderer/media/media_stream_audio_deliverer.h',
       'renderer/media/media_stream_audio_level_calculator.cc',
       'renderer/media/media_stream_audio_level_calculator.h',
+      'renderer/media/media_stream_audio_source.cc',
+      'renderer/media/media_stream_audio_source.h',
       'renderer/media/media_stream_audio_track.cc',
       'renderer/media/media_stream_audio_track.h',
       'renderer/media/media_stream_center.h',
@@ -326,6 +331,8 @@
       'renderer/media/media_stream_constraints_util.h',
       'renderer/media/media_stream_dispatcher.h',
       'renderer/media/media_stream_dispatcher_eventhandler.h',
+      'renderer/media/media_stream_source.cc',
+      'renderer/media/media_stream_source.h',
       'renderer/media/media_stream_track.cc',
       'renderer/media/media_stream_track.h',
       'renderer/media/midi_dispatcher.cc',
@@ -352,6 +359,8 @@
       'renderer/media/video_capture_message_filter.h',
       'renderer/media/web_media_element_source_utils.cc',
       'renderer/media/web_media_element_source_utils.h',
+      'renderer/media/webaudio_media_stream_source.cc',
+      'renderer/media/webaudio_media_stream_source.h',
       'renderer/media/webmediaplayer_ms.cc',
       'renderer/media/webmediaplayer_ms.h',
       'renderer/media/webmediaplayer_ms_compositor.cc',
@@ -651,18 +660,11 @@
       'renderer/media/media_stream_audio_processor.h',
       'renderer/media/media_stream_audio_processor_options.cc',
       'renderer/media/media_stream_audio_processor_options.h',
-      'renderer/media/media_stream_audio_sink_owner.cc',
-      'renderer/media/media_stream_audio_sink_owner.h',
-      'renderer/media/media_stream_audio_source.cc',
-      'renderer/media/media_stream_audio_source.h',
-      'renderer/media/media_stream_audio_track_sink.h',
       'renderer/media/media_stream_center.cc',
       'renderer/media/media_stream_dispatcher.cc',
       'renderer/media/media_stream_registry_interface.h',
       'renderer/media/media_stream_renderer_factory_impl.cc',
       'renderer/media/media_stream_renderer_factory_impl.h',
-      'renderer/media/media_stream_source.cc',
-      'renderer/media/media_stream_source.h',
       'renderer/media/media_stream_video_capturer_source.cc',
       'renderer/media/media_stream_video_capturer_source.h',
       'renderer/media/media_stream_video_renderer_sink.cc',
@@ -704,10 +706,6 @@
       'renderer/media/video_track_adapter.h',
       'renderer/media/video_track_recorder.cc',
       'renderer/media/video_track_recorder.h',
-      'renderer/media/webaudio_capturer_source.cc',
-      'renderer/media/webaudio_capturer_source.h',
-      'renderer/media/webrtc/media_stream_remote_audio_track.cc',
-      'renderer/media/webrtc/media_stream_remote_audio_track.h',
       'renderer/media/webrtc/media_stream_remote_video_source.cc',
       'renderer/media/webrtc/media_stream_remote_video_source.h',
       'renderer/media/webrtc/media_stream_track_metrics.cc',
@@ -716,22 +714,22 @@
       'renderer/media/webrtc/media_stream_video_webrtc_sink.h',
       'renderer/media/webrtc/peer_connection_dependency_factory.cc',
       'renderer/media/webrtc/peer_connection_dependency_factory.h',
+      'renderer/media/webrtc/peer_connection_remote_audio_source.cc',
+      'renderer/media/webrtc/peer_connection_remote_audio_source.h',
+      'renderer/media/webrtc/processed_local_audio_source.cc',
+      'renderer/media/webrtc/processed_local_audio_source.h',
       'renderer/media/webrtc/stun_field_trial.cc',
       'renderer/media/webrtc/stun_field_trial.h',
       'renderer/media/webrtc/track_observer.cc',
       'renderer/media/webrtc/track_observer.h',
-      'renderer/media/webrtc/webrtc_audio_sink_adapter.cc',
-      'renderer/media/webrtc/webrtc_audio_sink_adapter.h',
-      'renderer/media/webrtc/webrtc_local_audio_track_adapter.cc',
-      'renderer/media/webrtc/webrtc_local_audio_track_adapter.h',
+      'renderer/media/webrtc/webrtc_audio_sink.cc',
+      'renderer/media/webrtc/webrtc_audio_sink.h',
       'renderer/media/webrtc/webrtc_media_stream_adapter.cc',
       'renderer/media/webrtc/webrtc_media_stream_adapter.h',
       'renderer/media/webrtc/webrtc_video_capturer_adapter.cc',
       'renderer/media/webrtc/webrtc_video_capturer_adapter.h',
       'renderer/media/webrtc/webrtc_video_frame_adapter.cc',
       'renderer/media/webrtc/webrtc_video_frame_adapter.h',
-      'renderer/media/webrtc_audio_capturer.cc',
-      'renderer/media/webrtc_audio_capturer.h',
       'renderer/media/webrtc_audio_device_impl.cc',
       'renderer/media/webrtc_audio_device_impl.h',
       'renderer/media/webrtc_audio_device_not_impl.cc',
@@ -742,8 +740,6 @@
       'renderer/media/webrtc_identity_service.h',
       'renderer/media/webrtc_local_audio_source_provider.cc',
       'renderer/media/webrtc_local_audio_source_provider.h',
-      'renderer/media/webrtc_local_audio_track.cc',
-      'renderer/media/webrtc_local_audio_track.h',
       'renderer/media/webrtc_logging.cc',
       'renderer/media/webrtc_logging.h',
       'renderer/media/webrtc_uma_histograms.cc',