Refactoring: Use enum class for SerializationType

Source/core/xml/XMLSerializer.cpp

 /*
  *  Copyright (C) 2003, 2006 Apple Inc. All rights reserved.
  *  Copyright (C) 2006 Samuel Weinig (sam@webkit.org)
  *  Copyright (C) 2013 Samsung Electronics. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
  *  version 2 of the License, or (at your option) any later version.
  *
@@ skipping 11 matching lines @@
 #include "core/xml/XMLSerializer.h"
 
 #include "core/editing/MarkupAccumulator.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 String XMLSerializer::serializeToString(Node* root)
 {
     ASSERT(root);
-    MarkupAccumulator accumulator(DoNotResolveURLs, ForcedXML);
+    MarkupAccumulator accumulator(DoNotResolveURLs, SerializationType::ForcedXML);
     return serializeNodes<EditingStrategy>(accumulator, *root, IncludeNode);
 }
 
 } // namespace blink