Oilpan: move SVG property hierarchy to the heap.

Source/core/svg/SVGPathStringSource.h

Index: Source/core/svg/SVGPathStringSource.h
diff --git a/Source/core/svg/SVGPathStringSource.h b/Source/core/svg/SVGPathStringSource.h
index 73e6bbaf1e2e25f8176e8bc4ec958abf8c1c71ca..ec8dba7490ef47d0372c728f98d56aaf297a2a2e 100644
--- a/Source/core/svg/SVGPathStringSource.h
+++ b/Source/core/svg/SVGPathStringSource.h
@@ -29,13 +29,13 @@ namespace blink {
 
 class SVGPathStringSource final : public SVGPathSource {
 public:
-    static PassOwnPtr<SVGPathStringSource> create(const String& string)
+    static PassOwnPtrWillBeRawPtr<SVGPathStringSource> create(const String& string)
     {
-        return adoptPtr(new SVGPathStringSource(string));
+        return adoptPtrWillBeNoop(new SVGPathStringSource(string));
     }
 
 private:
-    SVGPathStringSource(const String&);
+    explicit SVGPathStringSource(const String&);
 
     virtual bool hasMoreData() const override;
     virtual bool moveToNextToken() override;