Fix sky include guards to match Chromium style

sky/engine/core/css/CSSSelector.h

 /*
  * Copyright (C) 1999-2003 Lars Knoll (knoll@kde.org)
  *               1999 Waldo Bastian (bastian@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010, 2013 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 CSSSelector_h
-#define CSSSelector_h
+#ifndef SKY_ENGINE_CORE_CSS_CSSSELECTOR_H_
+#define SKY_ENGINE_CORE_CSS_CSSSELECTOR_H_
 
 #include "sky/engine/core/dom/QualifiedName.h"
 #include "sky/engine/core/rendering/style/RenderStyleConstants.h"
 #include "sky/engine/wtf/OwnPtr.h"
 #include "sky/engine/wtf/PassOwnPtr.h"
 
 namespace blink {
     class CSSSelectorList;
 
     // This class represents a selector for a StyleRule.
@@ skipping 311 matching lines @@
     ASSERT(m_match != Tag);
     if (m_hasRareData)
         return m_data.m_rareData->m_value;
     // AtomicString is really just a StringImpl* so the cast below is safe.
     // FIXME: Perhaps call sites could be changed to accept StringImpl?
     return *reinterpret_cast<const AtomicString*>(&m_data.m_value);
 }
 
 } // namespace blink
 
-#endif // CSSSelector_h
+#endif  // SKY_ENGINE_CORE_CSS_CSSSELECTOR_H_