Remove unneeded uses of logging.h in header files.

base/non_thread_safe.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_NON_THREAD_SAFE_H__
 #define BASE_NON_THREAD_SAFE_H__
 
-#include "base/logging.h"
 #include "base/platform_thread.h"
 
 // A helper class used to help verify that methods of a class are
 // called from the same thread.  One can inherit from this class and use
 // CalledOnValidThread() to verify.
 //
 // This is intended to be used with classes that appear to be thread safe, but
 // aren't.  For example, a service or a singleton like the preferences system.
 //
 // Example:
@@ skipping 25 matching lines @@
   NonThreadSafe() {}
   ~NonThreadSafe() {}
 
   bool CalledOnValidThread() const {
     return true;
   }
 };
 #endif  // NDEBUG
 
 #endif  // BASE_NON_THREAD_SAFE_H__