Allow overriding the serialization rules in MarkupAccumulator

Source/core/xml/XMLSerializer.cpp

Index: Source/core/xml/XMLSerializer.cpp
diff --git a/Source/core/xml/XMLSerializer.cpp b/Source/core/xml/XMLSerializer.cpp
index a2e3187e0bed864fa8452e26df1bc485cde62354..11e9cd628717a101f06e7bd456ae5a3bb4032825 100644
--- a/Source/core/xml/XMLSerializer.cpp
+++ b/Source/core/xml/XMLSerializer.cpp
@@ -24,7 +24,7 @@
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
-#include "core/editing/markup.h"
+#include "core/editing/MarkupAccumulator.h"
 #include "wtf/text/WTFString.h"
 
 namespace WebCore {
@@ -36,7 +36,8 @@ String XMLSerializer::serializeToString(Node* node, ExceptionState& exceptionSta
         return String();
     }
 
-    return createMarkup(node);
+    MarkupAccumulator accumulator(0, DoNotResolveURLs, 0, ForcedXML);
+    return accumulator.serializeNodes(*node, IncludeNode);
 }
 
 } // namespace WebCore