Probing: Add support for exponential startup probing

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 "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/call/mock/mock_rtc_event_log.h"
 #include "webrtc/modules/pacing/mock/mock_paced_sender.h"
+#include "webrtc/modules/bitrate_controller/include/bitrate_controller.h"
 #include "webrtc/modules/congestion_controller/include/congestion_controller.h"
 #include "webrtc/modules/congestion_controller/include/mock/mock_congestion_controller.h"
 #include "webrtc/modules/remote_bitrate_estimator/include/mock/mock_remote_bitrate_observer.h"
 #include "webrtc/system_wrappers/include/clock.h"
 
 using testing::_;
 using testing::NiceMock;
 using testing::Return;
 using testing::SaveArg;
 using testing::StrictMock;
@@ skipping 139 matching lines @@
 
   // Let the pacer not be full next time the controller checks.
   EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
       .WillOnce(Return(PacedSender::kMaxQueueLengthMs - 1));
   EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps * 2, _, _));
   controller_->Process();
 }
 
 }  // namespace test
 }  // namespace webrtc