OVS + LB plugins clear device_id and device_owner if port is status down

[dan wendlandt]

these fields should not be modified by the L2 plugin itself, as they are set by the "consumer" of the port to indicate how the port is being used.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/11983

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/11983
Committed: http://github.com/openstack/quantum/commit/89942ed31568199f08ffa60982001f814eaa5b5e
Submitter: Jenkins
Branch: master

commit 89942ed31568199f08ffa60982001f814eaa5b5e
Author: Dan Wendlandt <email address hidden>
Date: Sat Aug 25 14:59:33 2012 -0700

    prevent OVS + LB plugins from clearing device_id and device_owner

    bug 1041669

    the fact that these plugins ever cleared this field is probably just a
    misunderstanding of how the field is supposed to be used, as I don't think
    it ever makes sense for the L2 plugin logic to change this field.

    Change-Id: Ie9579e2f88d322cfdce51a2ca126f4dfab680022