Comment 3 for bug 1666424

Reviewed: https://review.openstack.org/423584
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=1f5ee0e8942e4b77a89a00ee0249de5d5014e2bc
Submitter: Jenkins
Branch: master

commit 1f5ee0e8942e4b77a89a00ee0249de5d5014e2bc
Author: Kevin Benton <email address hidden>
Date: Fri Jan 20 21:23:05 2017 -0800

    Get rid of ML2 inheritance of delete_network

    In an effort to simplify the codebase, this eliminates
    all of the custom code in the ML2 delete_network
    method and leverages registry callbacks for network
    events.

    The only purpose of the remaining inheritance of the
    method is to leave the transaction guard on.

    Partial-Bug: #1666424
    Change-Id: Ib7d1c2081654dda82b5e015c71d20f378f3308f7