Generate the isSVG*Element() / toSVG*Element() helper functions

Source/core/rendering/svg/ReferenceFilterBuilder.cpp

Index: Source/core/rendering/svg/ReferenceFilterBuilder.cpp
diff --git a/Source/core/rendering/svg/ReferenceFilterBuilder.cpp b/Source/core/rendering/svg/ReferenceFilterBuilder.cpp
index 0155e295f9b2f99164d3c7e4c97c8d128132c700..784d43978233b8b09da544ee642feb652251b9e9 100644
--- a/Source/core/rendering/svg/ReferenceFilterBuilder.cpp
+++ b/Source/core/rendering/svg/ReferenceFilterBuilder.cpp
@@ -149,11 +149,7 @@ PassRefPtr<FilterEffect> ReferenceFilterBuilder::build(Filter* parentFilter, Ren
     ColorSpace filterColorSpace = ColorSpaceDeviceRGB;
     bool useFilterColorSpace = getSVGElementColorSpace(filterElement, filterColorSpace);
 
-    for (Element* child = ElementTraversal::firstWithin(*filterElement); child; child = ElementTraversal::nextSibling(*child)) {
-        if (!child->isSVGElement())
-            continue;
-
-        SVGElement* element = toSVGElement(child);
+    for (SVGElement* element = Traversal<SVGElement>::firstChild(*filterElement); element; element = Traversal<SVGElement>::nextSibling(*element)) {
         if (!element->isFilterEffect())
             continue;