Use DEFINE_NODE_TYPE_CASTS instead of using manual toSVGFooElement()

Source/core/svg/SVGClipPathElement.h

Index: Source/core/svg/SVGClipPathElement.h
diff --git a/Source/core/svg/SVGClipPathElement.h b/Source/core/svg/SVGClipPathElement.h
index 80f6be944eacaf03974c3d38c400daf0deb9f4fa..d098e69ba1bd95696ea6e9cddd0e4490dff2a7d6 100644
--- a/Source/core/svg/SVGClipPathElement.h
+++ b/Source/core/svg/SVGClipPathElement.h
@@ -56,11 +56,7 @@ private:
     END_DECLARE_ANIMATED_PROPERTIES
 };
 
-inline SVGClipPathElement* toSVGClipPathElement(Node* node)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!node || node->hasTagName(SVGNames::clipPathTag));
-    return static_cast<SVGClipPathElement*>(node);
-}
+DEFINE_NODE_TYPE_CASTS(SVGClipPathElement, hasTagName(SVGNames::clipPathTag));
 
 }