Remove unused thread.h include in trace_event_impl.h and fix IWUU.

ipc/ipc_test_channel_listener.cc

 // Copyright 2014 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_test_channel_listener.h"
 
+#include "base/message_loop/message_loop.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_sender.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace IPC {
 
 // static
 void TestChannelListener::SendOneMessage(IPC::Sender* sender,
                                          const char* text) {
   static int message_index = 0;
@@ skipping 36 matching lines @@
 }
 
 void TestChannelListener::SendNextMessage() {
   if (--messages_left_ <= 0)
     base::MessageLoop::current()->QuitWhenIdle();
   else
     SendOneMessage(sender_, "Foo");
 }
 
 }