Comment 1 for bug 1760303

Seeing this in a functional test:

http://logs.openstack.org/06/558006/1/check/nova-tox-functional/b74bcd5/testr_results.html.gz

2018-03-30 23:37:19,432 ERROR [nova.service] Service error occurred during cleanup_host
Traceback (most recent call last):
  File "nova/service.py", line 286, in stop
    self.manager.cleanup_host()
  File "nova/compute/manager.py", line 1166, in cleanup_host
    self.instance_events.cancel_all_events()
  File "nova/compute/manager.py", line 410, in cancel_all_events
    tag=tag, data={})
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/functional/local/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 307, in __init__
    setattr(self, key, kwargs[key])
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/functional/local/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 72, in setter
    field_value = field.coerce(self, name, value)
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/functional/local/lib/python2.7/site-packages/oslo_versionedobjects/fields.py", line 195, in coerce
    return self._type.coerce(obj, attr, value)
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/functional/local/lib/python2.7/site-packages/oslo_versionedobjects/fields.py", line 317, in coerce
    raise ValueError(msg)
ValueError: Field value network-vif-plugged-ce531f90-199f-48c0-816c is invalid
}}}