MediaStream audio sourcing: Bypass audio processing for non-WebRTC cases.

content/renderer/media/webrtc/processed_local_audio_track.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_RENDERER_MEDIA_WEBRTC_PROCESSED_LOCAL_AUDIO_TRACK_H_
+#define CONTENT_RENDERER_MEDIA_WEBRTC_PROCESSED_LOCAL_AUDIO_TRACK_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "content/renderer/media/media_stream_audio_track.h"
+
+namespace content {
+
+class WebRtcLocalAudioTrackAdapter;
+
+// A MediaStreamAudioTrack that also holds a WebRtcLocalAudioTrackAdapter and
+// provides an "adapter" bridge between the media stream object graph in the
+// content namespace and the separate object graph in the webrtc namespace.
+//
+// This class is instantiated by ProcessLocalAudioSource.
+class CONTENT_EXPORT ProcessedLocalAudioTrack
+    : NON_EXPORTED_BASE(public MediaStreamAudioTrack) {
+ public:
+  explicit ProcessedLocalAudioTrack(
+      const scoped_refptr<WebRtcLocalAudioTrackAdapter>& adapter);
+
+  ~ProcessedLocalAudioTrack() override;
+
+  // If |track| is an instance of ProcessedLocalAudioTrack, return a type-casted
+  // pointer to it.  Otherwise, return null.
+  static ProcessedLocalAudioTrack* From(MediaStreamAudioTrack* track);
+
+  WebRtcLocalAudioTrackAdapter* adapter() const { return adapter_.get(); }
+
+  // MediaStreamTrack override.
+  void SetEnabled(bool enabled) override;
+
+ private:
+  // MediaStreamAudioTrack override.
+  void* GetClassIdentifier() const final;
+
+  // All usage of libjingle is through this adapter. The adapter holds
+  // a pointer to this object, but no reference.
+  const scoped_refptr<WebRtcLocalAudioTrackAdapter> adapter_;
+
+  DISALLOW_COPY_AND_ASSIGN(ProcessedLocalAudioTrack);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MEDIA_WEBRTC_PROCESSED_LOCAL_AUDIO_TRACK_H_