Wire up send-side bandwidth estimation.

webrtc/video/video_loopback.cc

 /*
  *  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.
  */
 
@@ skipping 94 matching lines @@
     "trials are separated by \"/\"");
 
 DEFINE_int32(num_temporal_layers,
              0,
              "Number of temporal layers. Set to 1-4 to override.");
 
 size_t NumTemporalLayers() {
   return static_cast<size_t>(FLAGS_num_temporal_layers);
 }
 
+DEFINE_bool(send_side_bwe, false, "Use send-side bandwidth estimation");
 }  // namespace flags
 
 void Loopback() {
   test::Loopback::Config config{flags::Width(),
                                 flags::Height(),
                                 flags::Fps(),
                                 flags::MinBitrate(),
                                 flags::StartBitrate(),
                                 flags::MaxBitrate(),
                                 0,  // No min transmit bitrate.
                                 flags::Codec(),
                                 flags::NumTemporalLayers(),
                                 flags::LossPercent(),
                                 flags::LinkCapacity(),
                                 flags::QueueSize(),
                                 flags::AvgPropagationDelayMs(),
                                 flags::StdPropagationDelayMs(),
-                                flags::FLAGS_logs};
+                                flags::FLAGS_logs,
+                                flags::FLAGS_send_side_bwe};
   test::Loopback loopback(config);
   loopback.Run();
 }
 }  // namespace webrtc
 
 int main(int argc, char* argv[]) {
   ::testing::InitGoogleTest(&argc, argv);
   google::ParseCommandLineFlags(&argc, &argv, true);
   webrtc::test::InitFieldTrialsFromString(
       webrtc::flags::FLAGS_force_fieldtrials);
   webrtc::test::RunTest(webrtc::Loopback);
   return 0;
 }