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

chrome/renderer/extensions/cast_streaming_native_handler.cc

 // Copyright 2013 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 "chrome/renderer/extensions/cast_streaming_native_handler.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <algorithm>
 #include <functional>
@@ skipping 784 matching lines @@
   }
 
   media::VideoCaptureFormat capture_format(gfx::Size(max_width, max_height),
                                            fps, media::PIXEL_FORMAT_I420);
 
   video_config.target_frame_rate = fps;
   audio_config.target_frame_rate = 100;
 
   media::AudioParameters params(
       media::AudioParameters::AUDIO_PCM_LINEAR,
-      media::CHANNEL_LAYOUT_STEREO,
+      media::GuessChannelLayout(audio_config.channels),
       audio_config.rtp_timebase,  // sampling rate
-      16,
-      audio_config.rtp_timebase / audio_config.target_frame_rate);
+      16, audio_config.rtp_timebase / audio_config.target_frame_rate);
 
   if (!params.IsValid()) {
     args.GetIsolate()->ThrowException(v8::Exception::TypeError(
         v8::String::NewFromUtf8(args.GetIsolate(), kInvalidAudioParams)));
     return;
   }
 
   scoped_ptr<base::DictionaryValue> options;
   if (args.Length() >= 9) {
     scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
@@ skipping 37 matching lines @@
   context()->CallFunction(
       v8::Local<v8::Function>::New(isolate, function), 1, &arg);
 }
 
 
 void CastStreamingNativeHandler::AddTracksToMediaStream(
     const std::string& url,
     const media::AudioParameters& params,
     scoped_refptr<media::AudioCapturerSource> audio,
     scoped_ptr<media::VideoCapturerSource> video) {
-  content::AddAudioTrackToMediaStream(audio, params, true, true, url);
-  content::AddVideoTrackToMediaStream(std::move(video), true, true, url);
+  blink::WebMediaStream web_stream =
+      blink::WebMediaStreamRegistry::lookupMediaStreamDescriptor(GURL(url));
+  if (web_stream.isNull()) {
+    LOG(DFATAL) << "Stream not found.";
+    return;
+  }
+  if (!content::AddAudioTrackToMediaStream(
+          audio, params.sample_rate(), params.channel_layout(),
+          params.frames_per_buffer(), true /* is_remote */,
+          true /* is_readonly */, &web_stream)) {
+    LOG(ERROR) << "Failed to add Cast audio track to media stream.";
+  }
+  if (!content::AddVideoTrackToMediaStream(
+          std::move(video), true /* is_remote */, true /* is_readonly */,
+          &web_stream)) {
+    LOG(ERROR) << "Failed to add Cast video track to media stream.";
+  }
 }
 
 }  // namespace extensions