Add async trace events to trace progress of IPC messages

ipc/ipc_channel_posix.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ipc/ipc_channel_posix.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <stddef.h>
 #include <sys/types.h>
@@ skipping 613 matching lines @@
 
 bool Channel::ChannelImpl::Send(Message* message) {
   DVLOG(2) << "sending message @" << message << " on channel @" << this
            << " with type " << message->type()
            << " (" << output_queue_.size() << " in queue)";
 
 #ifdef IPC_MESSAGE_LOG_ENABLED
   Logging::GetInstance()->OnSendMessage(message, "");
 #endif  // IPC_MESSAGE_LOG_ENABLED
 
+  message->TraceMessageStep();
   output_queue_.push(message);
   if (!is_blocked_on_write_ && !waiting_connect_) {
     return ProcessOutgoingMessages();
   }
 
   return true;
 }
 
 int Channel::ChannelImpl::GetClientFileDescriptor() {
   base::AutoLock lock(client_pipe_lock_);
@@ skipping 542 matching lines @@
 
 
 #if defined(OS_LINUX)
 // static
 void Channel::SetGlobalPid(int pid) {
   ChannelImpl::SetGlobalPid(pid);
 }
 #endif  // OS_LINUX
 
 }  // namespace IPC