Oilpan: move SVG property hierarchy to the heap.

Source/core/svg/SVGFEOffsetElement.h

Index: Source/core/svg/SVGFEOffsetElement.h
diff --git a/Source/core/svg/SVGFEOffsetElement.h b/Source/core/svg/SVGFEOffsetElement.h
index c1a685b4874128ea559a6ae1ed5ac06838cde05f..aec5fa78eb7e50f432f240fb502b1655f826fda5 100644
--- a/Source/core/svg/SVGFEOffsetElement.h
+++ b/Source/core/svg/SVGFEOffsetElement.h
@@ -24,6 +24,7 @@
 #include "core/svg/SVGAnimatedNumber.h"
 #include "core/svg/SVGFilterPrimitiveStandardAttributes.h"
 #include "platform/graphics/filters/FEOffset.h"
+#include "platform/heap/Handle.h"
 
 namespace blink {
 
@@ -35,17 +36,20 @@ public:
     SVGAnimatedNumber* dx() { return m_dx.get(); }
     SVGAnimatedNumber* dy() { return m_dy.get(); }
     SVGAnimatedString* in1() { return m_in1.get(); }
+
+    virtual void trace(Visitor*) override;
+
 private:
     explicit SVGFEOffsetElement(Document&);
 
     bool isSupportedAttribute(const QualifiedName&);
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) override;
     virtual void svgAttributeChanged(const QualifiedName&) override;
-    virtual PassRefPtr<FilterEffect> build(SVGFilterBuilder*, Filter*) override;
+    virtual PassRefPtrWillBeRawPtr<FilterEffect> build(SVGFilterBuilder*, Filter*) override;
 
-    RefPtr<SVGAnimatedNumber> m_dx;
-    RefPtr<SVGAnimatedNumber> m_dy;
-    RefPtr<SVGAnimatedString> m_in1;
+    RefPtrWillBeMember<SVGAnimatedNumber> m_dx;
+    RefPtrWillBeMember<SVGAnimatedNumber> m_dy;
+    RefPtrWillBeMember<SVGAnimatedString> m_in1;
 };
 
 } // namespace blink