Move ThreadWrapper to ProcessThread in base.

webrtc/base/thread_checker_impl.cc

 /*
  *  Copyright (c) 2014 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.
  */
 
 // Borrowed from Chromium's src/base/threading/thread_checker_impl.cc.
 
 #include "webrtc/base/thread_checker_impl.h"
 
+#include "webrtc/base/platform_thread.h"
+
 namespace rtc {
 
 ThreadCheckerImpl::ThreadCheckerImpl() : valid_thread_(CurrentThreadRef()) {
 }
 
 ThreadCheckerImpl::~ThreadCheckerImpl() {
 }
 
 bool ThreadCheckerImpl::CalledOnValidThread() const {
   const PlatformThreadRef current_thread = CurrentThreadRef();
   CritScope scoped_lock(&lock_);
   if (!valid_thread_)  // Set if previously detached.
     valid_thread_ = current_thread;
   return IsThreadRefEqual(valid_thread_, current_thread);
 }
 
 void ThreadCheckerImpl::DetachFromThread() {
   CritScope scoped_lock(&lock_);
   valid_thread_ = 0;
 }
 
 }  // namespace rtc