Fix sky include guards to match Chromium style

sky/engine/core/dom/DocumentMarker.h

 /*
  * This file is part of the DOM implementation for WebCore.
  *
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * 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 DocumentMarker_h
-#define DocumentMarker_h
+#ifndef SKY_ENGINE_CORE_DOM_DOCUMENTMARKER_H_
+#define SKY_ENGINE_CORE_DOM_DOCUMENTMARKER_H_
 
 #include "sky/engine/platform/heap/Handle.h"
 #include "sky/engine/wtf/VectorTraits.h"
 #include "sky/engine/wtf/text/WTFString.h"
 
 namespace blink {
 
 class DocumentMarkerDetails;
 
 // A range of a node within a document that is "marked", such as the range of a misspelled word.
@@ skipping 112 matching lines @@
 {
 public:
     DocumentMarkerDetails() { }
     virtual ~DocumentMarkerDetails();
     virtual bool isDescription() const { return false; }
     virtual bool isTextMatch() const { return false; }
 };
 
 } // namespace blink
 
-#endif // DocumentMarker_h
+#endif  // SKY_ENGINE_CORE_DOM_DOCUMENTMARKER_H_