GObject.signal_chain_from_overridden

function signal_chain_from_overridden(instance_and_params: Array(Any), return_value: Any): void {
    // Gjs wrapper for g_signal_chain_from_overridden()
}

Calls the original class closure of a signal. This function should only be called from an overridden class closure; see GObject.signal_override_class_closure and GObject.signal_override_class_handler.

instance_and_params: the argument list of the signal emission. The first element in the array is a GObject.Value for the instance the signal is being emitted on. The rest are any arguments to be passed to the signal.
return_value: Location for the return value.