Comment 7 for bug 1843485

Reviewed: https://review.opendev.org/681945
Committed: https://git.openstack.org/cgit/openstack/networking-ovn/commit/?id=92142f3165806527e33a4544162ad4eb301e8436
Submitter: Zuul
Branch: master

commit 92142f3165806527e33a4544162ad4eb301e8436
Author: Flavio Fernandes <email address hidden>
Date: Thu Sep 12 18:32:34 2019 -0400

    Do not lose router logical port upon subnet add on the external net

    Prior to this patch, logical port used by the router to the external
    network was lost if subnet was added to that network. That was
    caused by missing explicit delete call in DelLRouterPortCommand.

    Also added functional test to exercise this particular code path:
      test_router::test_gateway_chassis_with_subnet_changes()

    Closes-Bug: #1843485
    Co-authored-by: Daniel Alvarez <email address hidden>
    Co-authored-by: Terry Wilson <email address hidden>
    Signed-off-by: Flavio Fernandes <email address hidden>

    Change-Id: I3e9d62ffc5eab396e983c0769e53d2d1f35644f6