Add GUARDED_BY in DirectTransport

webrtc/test/direct_transport.cc

 /*
  *  Copyright (c) 2013 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/test/direct_transport.h"
@@ skipping 76 matching lines @@
   // Constructor updates |next_scheduled_task_|, so it's guaranteed to
   // be initialized.
   task_queue_->CancelTask(next_scheduled_task_);
 }
 
 void DirectTransport::SetConfig(const FakeNetworkPipe::Config& config) {
   fake_network_.SetConfig(config);
 }
 
 void DirectTransport::StopSending() {
+  RTC_DCHECK_CALLED_SEQUENTIALLY(&sequence_checker_);
   task_queue_->CancelTask(next_scheduled_task_);
 }
 
 void DirectTransport::SetReceiver(PacketReceiver* receiver) {
   RTC_DCHECK_CALLED_SEQUENTIALLY(&sequence_checker_);
   fake_network_.SetReceiver(receiver);
 }
 
 bool DirectTransport::SendRtp(const uint8_t* data,
                               size_t length,
@@ skipping 37 matching lines @@
 
   fake_network_.Process();
 
   int64_t delay_ms = fake_network_.TimeUntilNextProcess();
   next_scheduled_task_ = task_queue_->PostDelayedTask([this]() {
     SendPackets();
   }, delay_ms);
 }
 }  // namespace test
 }  // namespace webrtc