Revert of Delete class MockCongestionController.

webrtc/modules/congestion_controller/congestion_controller_unittest.cc

 /*
  *  Copyright (c) 2016 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.
  */
 
 #include "webrtc/modules/congestion_controller/include/congestion_controller.h"
 #include "webrtc/logging/rtc_event_log/mock/mock_rtc_event_log.h"
 #include "webrtc/modules/bitrate_controller/include/bitrate_controller.h"
 #include "webrtc/modules/congestion_controller/congestion_controller_unittests_helper.h"
-#include "webrtc/modules/congestion_controller/include/mock/mock_congestion_observer.h"
+#include "webrtc/modules/congestion_controller/include/mock/mock_congestion_controller.h"
 #include "webrtc/modules/pacing/mock/mock_paced_sender.h"
 #include "webrtc/modules/remote_bitrate_estimator/include/bwe_defines.h"
 #include "webrtc/modules/remote_bitrate_estimator/include/mock/mock_remote_bitrate_observer.h"
 #include "webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.h"
 #include "webrtc/system_wrappers/include/clock.h"
 #include "webrtc/test/gmock.h"
 #include "webrtc/test/gtest.h"
 
 using testing::_;
 using testing::AtLeast;
@@ skipping 453 matching lines @@
   ASSERT_TRUE(target_bitrate_bps_);
 
   // Repeat, but this time with a building delay, and make sure that the
   // estimation is adjusted downwards.
   uint32_t bitrate_before_delay = *target_bitrate_bps_;
   PacketTransmissionAndFeedbackBlock(&seq_num, kRunTimeMs, 50);
   EXPECT_LT(*target_bitrate_bps_, bitrate_before_delay);
 }
 }  // namespace test
 }  // namespace webrtc