Automatic merge from submit-queue
proxy/iptables: don't sync proxy rules if services map didn't change
Build the service map in a separate testable function. Return that map instead of changing proxier.serviceMap directly. Use reflect.DeepEqual() to skip syncing proxy rules if nothing actually changed.
@thockin @kubernetes/rh-networking @kubernetes/sig-network-misc @timothysc @wojtek-t @jeremyeder @caseydavenport