* @param top the top-level zoneinfo resource bundle. This is used
* to lookup the rule that `res' may refer to, if there is one.
* @param res the resource bundle of the zone to be constructed
* @param top the top-level zoneinfo resource bundle. This is used
* to lookup the rule that `res' may refer to, if there is one.
* @param res the resource bundle of the zone to be constructed