Refactor MediaStreamManager to never output real device id. It now always output sourceId in the fo…

content/renderer/media/mock_media_stream_dispatcher.cc

 // Copyright (c) 2012 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/mock_media_stream_dispatcher.h"
 
 #include "base/strings/stringprintf.h"
 #include "content/public/common/media_stream_request.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 16 matching lines @@
     const StreamOptions& components,
     const GURL& url) {
   request_id_ = request_id;
 
   stream_label_ = base::StringPrintf("%s%d","local_stream",request_id);
   audio_array_.clear();
   video_array_.clear();
 
   if (IsAudioMediaType(components.audio_type)) {
     StreamDeviceInfo audio;
-    audio.device.id = "audio_device_id";
+    audio.device.id = base::StringPrintf("%s%d","audio_device_id", session_id_);
     audio.device.name = "microphone";
     audio.device.type = components.audio_type;
     audio.session_id = session_id_;
     audio_array_.push_back(audio);
   }
   if (IsVideoMediaType(components.video_type)) {
     StreamDeviceInfo video;
-    video.device.id = "video_device_id";
+    video.device.id = base::StringPrintf("%s%d","video_device_id", session_id_);
     video.device.name = "usb video camera";
     video.device.type = components.video_type;
     video.session_id = session_id_;
     video_array_.push_back(video);
   }
   ++request_stream_counter_;
 }
 
 void MockMediaStreamDispatcher::CancelGenerateStream(
   int request_id,
@@ skipping 22 matching lines @@
                                                 int index) {
   return -1;
 }
 
 int MockMediaStreamDispatcher::audio_session_id(const std::string& label,
                                                 int index) {
   return -1;
 }
 
 }  // namespace content