Prepare SVGDocumentExtensions::m_elementDependencies for oilpan

Source/core/svg/SVGPathElement.cpp

Index: Source/core/svg/SVGPathElement.cpp
diff --git a/Source/core/svg/SVGPathElement.cpp b/Source/core/svg/SVGPathElement.cpp
index feb4139f667eaaf70f0033f2bc73fe4636a8e4dc..c7478ef6419d67f870a2ad9dc4b764c3bd880d9d 100644
--- a/Source/core/svg/SVGPathElement.cpp
+++ b/Source/core/svg/SVGPathElement.cpp
@@ -236,9 +236,9 @@ void SVGPathElement::invalidateMPathDependencies()
 {
     // <mpath> can only reference <path> but this dependency is not handled in
     // markForLayoutAndParentResourceInvalidation so we update any mpath dependencies manually.
-    if (HashSet<SVGElement*>* dependencies = document().accessSVGExtensions().setOfElementsReferencingTarget(this)) {
-        HashSet<SVGElement*>::iterator end = dependencies->end();
-        for (HashSet<SVGElement*>::iterator it = dependencies->begin(); it != end; ++it) {
+    if (SVGElementSet* dependencies = document().accessSVGExtensions().setOfElementsReferencingTarget(this)) {
+        SVGElementSet::iterator end = dependencies->end();
+        for (SVGElementSet::iterator it = dependencies->begin(); it != end; ++it) {
             if (isSVGMPathElement(**it))
                 toSVGMPathElement(*it)->targetPathChanged();
         }