1. DomName('SVGTransformList.insertItemBefore')
  2. DocsEditable()
Transform insertItemBefore(Transform item, int index)

Source 

@DomName('SVGTransformList.insertItemBefore')
@DocsEditable()
Transform insertItemBefore(Transform item, int index) => wrap_jso(_blink.BlinkSVGTransformList.instance.insertItemBefore_Callback_2_(unwrap_jso(this), unwrap_jso(item), index));