FBTF: Remove unneeded headers from base/ (part 9)

base/lock_impl.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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_LOCK_IMPL_H_
 #define BASE_LOCK_IMPL_H_
 #pragma once
 
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #elif defined(OS_POSIX)
 #include <pthread.h>
 #endif
 
 #include "base/basictypes.h"
-#include "base/platform_thread.h"
 
 // This class implements the underlying platform-specific spin-lock mechanism
 // used for the Lock class.  Most users should not use LockImpl directly, but
 // should instead use Lock.
 class LockImpl {
  public:
 #if defined(OS_WIN)
   typedef CRITICAL_SECTION OSLockType;
 #elif defined(OS_POSIX)
   typedef pthread_mutex_t OSLockType;
@@ skipping 21 matching lines @@
 #endif
 
  private:
   OSLockType os_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(LockImpl);
 };
 
 
 #endif  // BASE_LOCK_IMPL_H_