Fix sky include guards to match Chromium style

sky/engine/wtf/Threading.h

 /*
  * Copyright (C) 2007, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Justin Haygood (jhaygood@reaktix.com)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef Threading_h
-#define Threading_h
+#ifndef SKY_ENGINE_WTF_THREADING_H_
+#define SKY_ENGINE_WTF_THREADING_H_
 
 #include <stdint.h>
 #include "sky/engine/wtf/WTFExport.h"
 
 // For portability, we do not use thread-safe statics natively supported by some compilers (e.g. gcc).
 #define AtomicallyInitializedStatic(T, name) \
     WTF::lockAtomicallyInitializedStaticMutex(); \
     static T name; \
     WTF::unlockAtomicallyInitializedStaticMutex();
 
 namespace WTF {
 
 typedef uint32_t ThreadIdentifier;
 
 // Called in the thread during initialization.
 // Helpful for platforms where the thread name must be set from within the thread.
 WTF_EXPORT void initializeCurrentThreadInternal(const char* threadName);
 
 WTF_EXPORT ThreadIdentifier currentThread();
 
 WTF_EXPORT void lockAtomicallyInitializedStaticMutex();
 WTF_EXPORT void unlockAtomicallyInitializedStaticMutex();
 
 } // namespace WTF
 
 using WTF::ThreadIdentifier;
 using WTF::currentThread;
 
-#endif // Threading_h
+#endif  // SKY_ENGINE_WTF_THREADING_H_