Fix sky include guards to match Chromium style

sky/engine/wtf/HashFunctions.h

 /*
  * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
-#ifndef WTF_HashFunctions_h
-#define WTF_HashFunctions_h
+#ifndef SKY_ENGINE_WTF_HASHFUNCTIONS_H_
+#define SKY_ENGINE_WTF_HASHFUNCTIONS_H_
 
 #include <stdint.h>
 #include "sky/engine/wtf/OwnPtr.h"
 #include "sky/engine/wtf/RefPtr.h"
 #include "sky/engine/wtf/StdLibExtras.h"
 
 namespace WTF {
 
     template<size_t size> struct IntTypes;
     template<> struct IntTypes<1> { typedef int8_t SignedType; typedef uint8_t UnsignedType; };
@@ skipping 198 matching lines @@
     // make PairHash the default hash function for pairs of arbitrary values.
 
     template<typename T, typename U> struct DefaultHash<std::pair<T, U> > { typedef PairHash<T, U> Hash; };
 
 } // namespace WTF
 
 using WTF::DefaultHash;
 using WTF::IntHash;
 using WTF::PtrHash;
 
-#endif // WTF_HashFunctions_h
+#endif  // SKY_ENGINE_WTF_HASHFUNCTIONS_H_