In change [1] we modified _heal_instance_info_cache periodic task
to use Neutron point of view while rebuilding InstanceInfoCache
objects.
The crucial point was how we know the previous order of ports, if
the cache was broken. We decided to use VirtualInterfaceList objects
as source of port order.
For instances older than Newton VirtualInterface objects doesn't
exist, so we need to introduce a way of creating it.
This script should be executed while upgrading to Stein release.
[1] https://review.openstack.org/#/c/591607
Change-Id: Ic26d4ce3d071691a621d3c925dc5cd436b2005f1
Related-Bug: 1751923