Deal with negative cache responses when using dns_db_findrdataset().
Deal with negative cache responses when using dns_db_findrdataset().

each/bind9-collab,each/bind9-collab,each/bind9-collab,pecharmin/bind9,pecharmin/bind9,pecharmin/bind9,each/bind9-collab,pecharmin/bind9,pecharmin/bind9,each/bind9-collab,each/bind9-collab,pecharmin/bind9