Revert 212948 "Made MessagePump a non-thread safe class."

trunk/src/base/message_loop/message_pump_default.cc

 // Copyright (c) 2006-2008 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 "base/message_loop/message_pump_default.h"
 
 #include "base/logging.h"
 #include "base/threading/thread_restrictions.h"
 
 #if defined(OS_MACOSX)
 #include "base/mac/scoped_nsautorelease_pool.h"
 #endif
 
 namespace base {
 
 MessagePumpDefault::MessagePumpDefault()
     : keep_running_(true),
       event_(false, false) {
 }
 
-MessagePumpDefault::~MessagePumpDefault() {
-}
-
 void MessagePumpDefault::Run(Delegate* delegate) {
   DCHECK(keep_running_) << "Quit must have been called outside of Run!";
 
   for (;;) {
 #if defined(OS_MACOSX)
     mac::ScopedNSAutoreleasePool autorelease_pool;
 #endif
 
     bool did_work = delegate->DoWork();
     if (!keep_running_)
@@ skipping 45 matching lines @@
 
 void MessagePumpDefault::ScheduleDelayedWork(
     const TimeTicks& delayed_work_time) {
   // We know that we can't be blocked on Wait right now since this method can
   // only be called on the same thread as Run, so we only need to update our
   // record of how long to sleep when we do sleep.
   delayed_work_time_ = delayed_work_time;
 }
 
 }  // namespace base