Comment 0 for bug 1533013

Some brilliant individual introduced a regression during a refactor (https://review.openstack.org/#/c/263471/) that causes an exception to be raised when an unbound port is deleted. For example:

neutron port-create --name=port some_network
neutron port-delete port
Deleted port: port

In the neutron-server log we can see:
http://paste.openstack.org/show/483517/

Apart from the scary TRACE there's no real implications. What should have happened is an early return, so the l2pop mech driver shouldn't be doing anything in this case, and it's spamming the log with bogus information instead.