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 330609deed5c1df78d697f54f2adaab62481dbfe..933cc4f9f25e7a6bdc69be614a1dcdb97cbe4d50 100644
--- a/content/content_renderer.gypi
+++ b/content/content_renderer.gypi
@@ -317,10 +317,15 @@
       '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',
@@ -328,6 +333,8 @@
       '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',
@@ -354,6 +361,8 @@
       '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',
@@ -653,18 +662,11 @@
       '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',
@@ -706,10 +708,6 @@
       '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',
@@ -718,22 +716,22 @@
       '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',
@@ -744,8 +742,6 @@
       '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',