Wire-up BWE feedback for audio receive streams.

Also wires up receiving transport sequence numbers.

BUG=webrtc:5263
R=mflodman@webrtc.org, pbos@webrtc.org, solenberg@webrtc.org

Review URL: https://codereview.webrtc.org/1535963002 .

Cr-Commit-Position: refs/heads/master@{#11220}

webrtc/modules/bitrate_controller/include/mock/mock_bitrate_controller.h

@@ -0,0 +1,30 @@
+/*
+ *  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_MODULES_BITRATE_CONTROLLER_INCLUDE_MOCK_MOCK_BITRATE_CONTROLLER_H_
+#define WEBRTC_MODULES_BITRATE_CONTROLLER_INCLUDE_MOCK_MOCK_BITRATE_CONTROLLER_H_
+
+#include "testing/gmock/include/gmock/gmock.h"
+#include "webrtc/modules/bitrate_controller/include/bitrate_controller.h"
+
+namespace webrtc {
+namespace test {
+
+class MockBitrateObserver : public BitrateObserver {
+ public:
+  MOCK_METHOD3(OnNetworkChanged,
+               void(uint32_t bitrate_bps,
+                    uint8_t fraction_loss,
+                    int64_t rtt_ms));
+};
+}  // namespace test
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_BITRATE_CONTROLLER_INCLUDE_MOCK_MOCK_BITRATE_CONTROLLER_H_