Change the default rtcp mux policy from negotiate to require.

components/test_runner/mock_webrtc_peer_connection_handler.cc

 // Copyright 2014 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 "components/test_runner/mock_webrtc_peer_connection_handler.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 441 matching lines @@
 
 WebRTCSessionDescription MockWebRTCPeerConnectionHandler::remoteDescription() {
   return remote_description_;
 }
 
 bool MockWebRTCPeerConnectionHandler::setConfiguration(
     const WebRTCConfiguration& configuration) {
   return true;
 }
 
-void MockWebRTCPeerConnectionHandler::logSelectedRtcpMuxPolicy(
-    blink::RtcpMuxPolicy selectedRtcpMuxPolicy) {}
-
 bool MockWebRTCPeerConnectionHandler::addICECandidate(
     const WebRTCICECandidate& ice_candidate) {
   client_->didGenerateICECandidate(ice_candidate);
   return true;
 }
 
 bool MockWebRTCPeerConnectionHandler::addICECandidate(
     const WebRTCVoidRequest& request,
     const WebRTCICECandidate& ice_candidate) {
   PostRequestResult(request);
@@ skipping 92 matching lines @@
     const WebMediaStreamTrack& track) {
   return new MockWebRTCDTMFSenderHandler(track, interfaces_->GetDelegate());
 }
 
 void MockWebRTCPeerConnectionHandler::stop() {
   stopped_ = true;
   weak_factory_.InvalidateWeakPtrs();
 }
 
 }  // namespace test_runner