Intorudce DECLARE/DEFINE_ELEMENT_FACTORY_WITH_TAGNAME macros.

Source/core/svg/SVGUnknownElement.h

Index: Source/core/svg/SVGUnknownElement.h
diff --git a/Source/core/svg/SVGUnknownElement.h b/Source/core/svg/SVGUnknownElement.h
index 0b3ddd78eb6421ed0bd6d32b4433208e6937f958..d99ac032d11a237f85e51eeb4112f0dc7c3c9a6b 100644
--- a/Source/core/svg/SVGUnknownElement.h
+++ b/Source/core/svg/SVGUnknownElement.h
@@ -43,10 +43,7 @@ namespace WebCore {
 // false to make sure we don't attempt to render such elements.
 class SVGUnknownElement FINAL : public SVGElement {
 public:
-    static PassRefPtrWillBeRawPtr<SVGUnknownElement> create(const QualifiedName& tagName, Document& document)
-    {
-        return adoptRefWillBeRefCountedGarbageCollected(new SVGUnknownElement(tagName, document));
-    }
+    DECLARE_ELEMENT_FACTORY_WITH_TAGNAME(SVGUnknownElement);
 
 private:
     SVGUnknownElement(const QualifiedName&, Document&);