Support cancellation of request for opening device.

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 31 matching lines @@
     StreamDeviceInfo video;
     video.device.id = "video_device_id";
     video.device.name = "usb video camera";
     video.device.type = components.video_type;
     video.session_id = request_id;
     video_array_.push_back(video);
   }
   ++request_stream_counter_;
 }
 
-void MockMediaStreamDispatcher::CancelGenerateStream(int request_id) {
+void MockMediaStreamDispatcher::CancelGenerateStream(
+  int request_id,
+  const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler) {
   EXPECT_EQ(request_id, request_id_);
 }
 
 void MockMediaStreamDispatcher::StopStream(const std::string& label) {
   ++stop_stream_counter_;
 }
 
 bool MockMediaStreamDispatcher::IsStream(const std::string& label) {
   return true;
 }
 
 int MockMediaStreamDispatcher::video_session_id(const std::string& label,
                                                 int index) {
   return -1;
 }
 
 int MockMediaStreamDispatcher::audio_session_id(const std::string& label,
                                                 int index) {
   return -1;
 }
 
 }  // namespace content