Fix sky include guards to match Chromium style

sky/engine/core/dom/TreeShared.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2012 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 TreeShared_h
-#define TreeShared_h
+#ifndef SKY_ENGINE_CORE_DOM_TREESHARED_H_
+#define SKY_ENGINE_CORE_DOM_TREESHARED_H_
 
 #include "sky/engine/public/platform/WebPrivatePtr.h"
 #include "sky/engine/wtf/Assertions.h"
 #include "sky/engine/wtf/MainThread.h"
 #include "sky/engine/wtf/Noncopyable.h"
 
 namespace blink {
 
 #if ENABLE(SECURITY_ASSERT)
 template<typename NodeType> class TreeShared;
@@ skipping 77 matching lines @@
     ASSERT_WITH_SECURITY_IMPLICATION(!object->m_deletionHasBegun);
 #if ENABLE(ASSERT)
     ASSERT(!object->m_inRemovedLastRefFunction);
     object->m_adoptionIsRequired = false;
 #endif
 }
 #endif
 
 }
 
-#endif // TreeShared.h
+#endif  // SKY_ENGINE_CORE_DOM_TREESHARED_H_