No recordset notifications emitted for nameserver changes

[Steve McLellan]

If I update the pool nameserver list, new NS records will be added to any recordsets belonging to affected zones, but no notifications are received indicating changes to the recordsets. For instance:

$ designate record-list 92702ce9-b92b-4a52-8272-9294e916a4ec

  | id | type | name | data
  | e863abcb-a2b1-4666-99f2-b34fbb82dd46 | SOA | example.com. | ns1.devstack.org. steve.mclellan.hpe.com. 1466536742 3569 600 86400 3600 |
  | fcd802ec-908b-46ae-bd59-4b9cb71bc370 | NS | example.com. | ns1.devstack.org.

If I then add ns2.devstack.org to the ns_records list and update the pools:

  $ designate-manage pool update --file designate-pool-conf.yaml
  $ designate record-list 92702ce9-b92b-4a52-8272-9294e916a4ec

  | id | type | name | data
  | e863abcb-a2b1-4666-99f2-b34fbb82dd46 | SOA | sjm.example.com. | ns1.devstack.org. steve.mclellan.hpe.com. 1466536970 3569 600 86400 3600 |
  | d77a2c6f-2d90-44f8-a48d-4e21793de019 | NS | sjm.example.com. | ns2.devstack.org.
  | fcd802ec-908b-46ae-bd59-4b9cb71bc370 | NS | sjm.example.com. | ns1.devstack.org.

I see event notifications for dns.domain.update, dns.zone.update (X2), dns.domain.update. There should be recordset.update events also. This applies equally to deleting or changing nameservers.