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

content/renderer/media/webrtc/processed_local_audio_track.cc

Index: content/renderer/media/webrtc/processed_local_audio_track.cc
diff --git a/content/renderer/media/webrtc/processed_local_audio_track.cc b/content/renderer/media/webrtc/processed_local_audio_track.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e1cf37624eb9a1948c4c92d2165f2802b6f6d12a
--- /dev/null
+++ b/content/renderer/media/webrtc/processed_local_audio_track.cc
@@ -0,0 +1,50 @@
+// 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.
+
+#include "content/renderer/media/webrtc/processed_local_audio_track.h"
+
+#include "content/renderer/media/webrtc/webrtc_local_audio_track_adapter.h"
+
+namespace content {
+
+namespace {
+// Used as an identifier for ProcessedLocalAudioTrack::From().
+void* const kClassIdentifier = const_cast<void**>(&kClassIdentifier);
+}  // namespace
+
+ProcessedLocalAudioTrack::ProcessedLocalAudioTrack(
+    const scoped_refptr<WebRtcLocalAudioTrackAdapter>& adapter)
+    : MediaStreamAudioTrack(true),
+      adapter_(adapter) {
+  DCHECK(adapter_.get());
+  adapter_->SetMediaStreamAudioTrack(this);
+
+  DVLOG(1) << "ProcessedLocalAudioTrack::ProcessedLocalAudioTrack()";
+}
+
+ProcessedLocalAudioTrack::~ProcessedLocalAudioTrack() {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  DVLOG(1) << "ProcessedLocalAudioTrack::~ProcessedLocalAudioTrack()";
+  adapter_->SetMediaStreamAudioTrack(nullptr);
+}
+
+// static
+ProcessedLocalAudioTrack* ProcessedLocalAudioTrack::From(
+    MediaStreamAudioTrack* track) {
+  if (track && track->GetClassIdentifier() == kClassIdentifier)
+    return static_cast<ProcessedLocalAudioTrack*>(track);
+  return nullptr;
+}
+
+void ProcessedLocalAudioTrack::SetEnabled(bool enabled) {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  MediaStreamAudioTrack::SetEnabled(enabled);
+  adapter_->set_enabled(enabled);
+}
+
+void* ProcessedLocalAudioTrack::GetClassIdentifier() const {
+  return kClassIdentifier;
+}
+
+}  // namespace content