[SVG] SVGAnimatedString{,List} migration to new SVG property impl.

Source/core/svg/SVGMPathElement.h

Index: Source/core/svg/SVGMPathElement.h
diff --git a/Source/core/svg/SVGMPathElement.h b/Source/core/svg/SVGMPathElement.h
index 6d88206cf34c8d19cdaf14484749b6e180b6283f..334714a9daf082493b7dde4397dbb92109b9b6b7 100644
--- a/Source/core/svg/SVGMPathElement.h
+++ b/Source/core/svg/SVGMPathElement.h
@@ -40,6 +40,7 @@ public:
     SVGPathElement* pathElement();
 
     void targetPathChanged();
+    SVGAnimatedString* href() { return m_href.get(); }
 
 private:
     explicit SVGMPathElement(Document&);
@@ -56,8 +57,8 @@ private:
     virtual bool rendererIsNeeded(const RenderStyle&) OVERRIDE { return false; }
     void notifyParentOfPathChange(ContainerNode*);
 
+    RefPtr<SVGAnimatedString> m_href;
     BEGIN_DECLARE_ANIMATED_PROPERTIES(SVGMPathElement)
-        DECLARE_ANIMATED_STRING(Href, href)
     END_DECLARE_ANIMATED_PROPERTIES
 };