Open backdoor in VoiceEngineImpl to get at the actual voe::Channel objects from an ID.

webrtc/test/mock_voe_channel_proxy.h

 /*
  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#ifndef WEBRTC_TEST_HISTOGRAM_H_
-#define WEBRTC_TEST_HISTOGRAM_H_
+#ifndef WEBRTC_AUDIO_MOCK_VOE_CHANNEL_PROXY_H_
+#define WEBRTC_AUDIO_MOCK_VOE_CHANNEL_PROXY_H_
 
-#include <string>
+#include "testing/gmock/include/gmock/gmock.h"
+#include "webrtc/voice_engine/channel_proxy.h"
 
 namespace webrtc {
 namespace test {
 
-// Returns the last added sample to a histogram (or -1 if the histogram is not
-// found).
-int LastHistogramSample(const std::string& name);
-
-// Returns the number of added samples to a histogram.
-int NumHistogramSamples(const std::string& name);
-
-// Removes all histograms.
-void ClearHistograms();
-
+class MockVoEChannelProxy : public voe::ChannelProxy {
+ public:
+  MOCK_METHOD1(SetRTCPStatus, void(bool enable));
+  MOCK_METHOD1(SetLocalSSRC, void(uint32_t ssrc));
+  MOCK_METHOD1(SetRTCP_CNAME, void(const std::string& c_name));
+};
 }  // namespace test
 }  // namespace webrtc
 
-#endif  // WEBRTC_TEST_HISTOGRAM_H_
-
+#endif  // WEBRTC_AUDIO_MOCK_VOE_CHANNEL_PROXY_H_