[neutron][networking-ovn] The function provider_network_attribute_updates_supported is breaking networking-ovn gate

[Reedip]

Networking-OVN's gate broke [0] after [1] was merged due to the missing definition of provider_network_attribute_updates_supported in [2]. In my opinion, it would serve a better purpose to have this definition in the base class itself.

[0]http://paste.openstack.org/show/749041/. The logs have been retrieved from
http://logs.openstack.org/13/649213/4/check/openstack-tox-py27/a70c92b/job-output.txt.gz#_2019-04-05_11_09_08_715122

[1]I2595335d6fbc51562b070f14eaeaadf49cf7c418

[2]https://github.com/openstack/neutron-lib/blob/master/neutron_lib/plugins/ml2/api.py#L37

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/651175

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.openstack.org/651177

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/651175
Committed: https://git.openstack.org/cgit/openstack/neutron-lib/commit/?id=3fd0a3c4d7d54ba438746365653a9d379c842f08
Submitter: Zuul
Branch: master

commit 3fd0a3c4d7d54ba438746365653a9d379c842f08
Author: Rodolfo Alonso Hernandez <email address hidden>
Date: Tue Apr 9 09:35:54 2019 +0000

    Rehome provider_network_attribute_updates_supported to API definition

    Rehomed provider_network_attribute_updates_supported to
    plugins.ml2.api.MechanismDriver, in order to be inherited in other
    mechanism drivers.

    Change-Id: I145861b0ca356e3e27495fb2b0205f6e8339a964
    Closes-Bug: #1823865

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron-lib 1.26.0 release.

[OpenStack Infra (hudson-openstack)]

Change abandoned by Rodolfo Alonso Hernandez (<email address hidden>) on branch: master
Review: https://review.opendev.org/651177
Reason: Addressed in https://review.opendev.org/#/c/655347/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/655347
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=cfaf5cc1e19a88a9e272967d93b89279284af12c
Submitter: Zuul
Branch: master

commit cfaf5cc1e19a88a9e272967d93b89279284af12c
Author: Rodolfo Alonso Hernandez <email address hidden>
Date: Wed Apr 24 07:44:29 2019 +0000

    Rehome provider_network_attribute_updates_supported to API definition

    Rehomed provider_network_attribute_updates_supported to
    plugins.ml2.api.MechanismDriver, in order to be inherited in other
    mechanism drivers.

    Related-Bug: #1823865

    Change-Id: I9be175aa2334111a17d8fec874d2331e23923837