Reduce header dependencies in base/

base/waitable_event.h

 // 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.
 
 #ifndef BASE_WAITABLE_EVENT_H_
 #define BASE_WAITABLE_EVENT_H_
 
 #include "base/basictypes.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 
 #if defined(OS_POSIX)
 #include <list>
 #include <utility>
-#include "base/condition_variable.h"
 #include "base/lock.h"
 #include "base/ref_counted.h"
 #endif
 
-#include "base/message_loop.h"
-
 namespace base {
 
 // This replaces INFINITE from Win32
 static const int kNoTimeout = -1;
 
 class TimeDelta;
 
 // A WaitableEvent can be a useful thread synchronization tool when you want to
 // allow one thread to wait for another thread to finish some work. For
 // non-Windows systems, this can only be used from within a single address
@@ skipping 137 matching lines @@
   static size_t EnqueueMany(WaiterAndIndex* waitables,
                             size_t count, Waiter* waiter);
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(WaitableEvent);
 };
 
 }  // namespace base
 
 #endif  // BASE_WAITABLE_EVENT_H_