gtk/menu_shell.go
func (v *MenuShell) Append(child IMenuItem) {
	C.gtk_menu_shell_append(v.native(), child.toWidget())
}
func (v *MenuShell) Append(child IMenuItem) {
	C.gtk_menu_shell_append(v.native(), child.toWidget())
}
// Append is a wrapper around gtk_menu_shell_append().