Comment 10 for bug 1407959

With [1], I don't think the error in the description will report anymore. When I debug the code, I found that all agents(metadata, dhcp, l3, ovs) are returned for get_dvr_active_network_ports and get_nondvr_active_network_ports. So, the query still need to refine.

[1] https://review.openstack.org/#/c/237785