Oilpan: move SVG property hierarchy to the heap.

Source/core/svg/SVGAnimatedString.h

Index: Source/core/svg/SVGAnimatedString.h
diff --git a/Source/core/svg/SVGAnimatedString.h b/Source/core/svg/SVGAnimatedString.h
index 106e3aa20976e207ce291f0829b1e604c6dc8f95..db0d9a20fb93b2bc2cdc3c4fa55b238784e441cc 100644
--- a/Source/core/svg/SVGAnimatedString.h
+++ b/Source/core/svg/SVGAnimatedString.h
@@ -38,13 +38,13 @@ namespace blink {
 
 class SVGAnimatedString final : public SVGAnimatedProperty<SVGString> {
 public:
-    static PassRefPtr<SVGAnimatedString> create(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<SVGString> initialValue)
+    static PassRefPtrWillBeRawPtr<SVGAnimatedString> create(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtrWillBeRawPtr<SVGString> initialValue)
     {
-        return adoptRef(new SVGAnimatedString(contextElement, attributeName, initialValue));
+        return adoptRefWillBeNoop(new SVGAnimatedString(contextElement, attributeName, initialValue));
     }
 
 protected:
-    SVGAnimatedString(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<SVGString> initialValue)
+    SVGAnimatedString(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtrWillBeRawPtr<SVGString> initialValue)
         : SVGAnimatedProperty<SVGString>(contextElement, attributeName, initialValue)
     {
     }