Add tracing to MessageQueue::Dispatch.

webrtc/base/messagequeue.cc

 /*
  *  Copyright 2004 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 <algorithm>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/common.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/messagequeue.h"
+#include "webrtc/base/trace_event.h"
 
 namespace rtc {
 
 const uint32_t kMaxMsgLatency = 150;  // 150 ms
 
 //------------------------------------------------------------------
 // MessageQueueManager
 
 MessageQueueManager* MessageQueueManager::instance_ = NULL;
 
@@ skipping 408 matching lines @@
       }
     } else {
       *new_end++ = *it;
     }
   }
   dmsgq_.container().erase(new_end, dmsgq_.container().end());
   dmsgq_.reheap();
 }
 
 void MessageQueue::Dispatch(Message *pmsg) {
+  TRACE_EVENT0("webrtc", "MessageQueue::Dispatch");
   pmsg->phandler->OnMessage(pmsg);
 }
 
 }  // namespace rtc