gtk/gtk.go
func (v *ListStore) InsertBefore(sibling *TreeIter) *TreeIter {
	var ti C.GtkTreeIter
	C.gtk_list_store_insert_before(v.native(), &ti, sibling.native())
	iter := &TreeIter{ti}
	return iter
}
func (v *ListStore) InsertBefore(sibling *TreeIter) *TreeIter {
	var ti C.GtkTreeIter
	C.gtk_list_store_insert_before(v.native(), &ti, sibling.native())
	iter := &TreeIter{ti}
	return iter
}
// InsertBefore() is a wrapper around gtk_list_store_insert_before().