LBaaS: apply default provider for existing pools

[Oleg Bondarev]

For pools that were created before service providers support 'provider' field is empty. This causes neutron start failure with the following error:

Delete associated loadbalancer pools before removing providers ['']

I think that for such pools we can safely apply the default provider (haproxy) on start as it is the only provider supported at the moment.

[Eugene Nikanorov (enikanorov)]

That should have been addressed by the ability of having unassociated pools plus the ability to associate provider.
Need to revisit the logic in Icehouse and make it more flexible.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/45040

[Eugene Nikanorov (enikanorov)]

I think this can be closed as more than a release cycle has passed since providers were introduced to API.

[Jacob Godin (jacobgodin)]

I would like to propose re-opening this bug. We ran into it today when upgrading Neutron from G->J. The patch provided solved the issue.

[Launchpad Janitor (janitor)]

[Expired for neutron because there has been no activity for 60 days.]