Allow mocking SendSideCongestionController for Call tests.

webrtc/modules/congestion_controller/send_side_congestion_controller.cc

 /*
  *  Copyright (c) 2012 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 28 matching lines @@
   if (*max_bitrate_bps > 0)
     *max_bitrate_bps = std::max(*min_bitrate_bps, *max_bitrate_bps);
   if (*bitrate_bps > 0)
     *bitrate_bps = std::max(*min_bitrate_bps, *bitrate_bps);
 }
 
 }  // namespace
 
 SendSideCongestionController::SendSideCongestionController(
     const Clock* clock,
-    Observer* observer,
     RtcEventLog* event_log,
     PacketRouter* packet_router)
     : SendSideCongestionController(
           clock,
-          observer,
           event_log,
           std::unique_ptr<PacedSender>(
               new PacedSender(clock, packet_router, event_log))) {}
 
 SendSideCongestionController::SendSideCongestionController(
     const Clock* clock,
-    Observer* observer,
     RtcEventLog* event_log,
     std::unique_ptr<PacedSender> pacer)
     : clock_(clock),
-      observer_(observer),
       event_log_(event_log),
       pacer_(std::move(pacer)),
       bitrate_controller_(
           BitrateController::CreateBitrateController(clock_, event_log)),
       probe_controller_(new ProbeController(pacer_.get(), clock_)),
       retransmission_rate_limiter_(
           new RateLimiter(clock, kRetransmitWindowSizeMs)),
       transport_feedback_adapter_(clock_),
       last_reported_bitrate_bps_(0),
       last_reported_fraction_loss_(0),
@@ skipping 235 matching lines @@
 bool SendSideCongestionController::IsSendQueueFull() const {
   return pacer_->ExpectedQueueTimeMs() > PacedSender::kMaxQueueLengthMs;
 }
 
 bool SendSideCongestionController::IsNetworkDown() const {
   rtc::CritScope cs(&network_state_lock_);
   return network_state_ == kNetworkDown;
 }
 
 }  // namespace webrtc