Oilpan: move SVG property hierarchy to the heap.

Source/core/svg/SVGFEMergeElement.cpp

Index: Source/core/svg/SVGFEMergeElement.cpp
diff --git a/Source/core/svg/SVGFEMergeElement.cpp b/Source/core/svg/SVGFEMergeElement.cpp
index 93df548ac1c35d2b10d9a87a73ee0b60e1464d20..3b980369c564e4eb3fe2548a421dc81ad6e79874 100644
--- a/Source/core/svg/SVGFEMergeElement.cpp
+++ b/Source/core/svg/SVGFEMergeElement.cpp
@@ -37,9 +37,9 @@ inline SVGFEMergeElement::SVGFEMergeElement(Document& document)
 
 DEFINE_NODE_FACTORY(SVGFEMergeElement)
 
-PassRefPtr<FilterEffect> SVGFEMergeElement::build(SVGFilterBuilder* filterBuilder, Filter* filter)
+PassRefPtrWillBeRawPtr<FilterEffect> SVGFEMergeElement::build(SVGFilterBuilder* filterBuilder, Filter* filter)
 {
-    RefPtr<FilterEffect> effect = FEMerge::create(filter);
+    RefPtrWillBeRawPtr<FilterEffect> effect = FEMerge::create(filter);
     FilterEffectVector& mergeInputs = effect->inputEffects();
     for (SVGFEMergeNodeElement* element = Traversal<SVGFEMergeNodeElement>::firstChild(*this); element; element = Traversal<SVGFEMergeNodeElement>::nextSibling(*element)) {
         FilterEffect* mergeEffect = filterBuilder->getEffectById(AtomicString(element->in1()->currentValue()->value()));