[oilpan] Implement accept methods to trace the class hierarchy of SVGElement and all sub-classes.

Source/core/svg/SVGFETurbulenceElement.h

Index: Source/core/svg/SVGFETurbulenceElement.h
diff --git a/Source/core/svg/SVGFETurbulenceElement.h b/Source/core/svg/SVGFETurbulenceElement.h
index 23a34f016f0ba64591f147d4f7d86f2c844c32a8..2e3fe04775d8938b72ddbd899bbfb8ff0318703b 100644
--- a/Source/core/svg/SVGFETurbulenceElement.h
+++ b/Source/core/svg/SVGFETurbulenceElement.h
@@ -98,6 +98,8 @@ class SVGFETurbulenceElement : public SVGFilterPrimitiveStandardAttributes {
 public:
     static PassRefPtr<SVGFETurbulenceElement> create(const QualifiedName&, const Handle<Document>&);
 
+    virtual void accept(Visitor* visitor) const OVERRIDE { SVGFilterPrimitiveStandardAttributes::accept(visitor); }
+
 private:
     SVGFETurbulenceElement(const QualifiedName&, const Handle<Document>&);