Comment 12 for bug 1843708

Reviewed: https://review.opendev.org/743264
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=0bc5a4ecb524a73aacb5d0dd2887799885bdbb14
Submitter: Zuul
Branch: stable/stein

commit 0bc5a4ecb524a73aacb5d0dd2887799885bdbb14
Author: Takashi NATSUME <email address hidden>
Date: Thu Sep 19 15:57:44 2019 +0900

    objects: Update keypairs when saving an instance

    The keypair of a server is updated when rebuilding the server with a
    keypair. This function has been added since API microversion 2.54.
    However the 'keypairs' of the instance object is not saved when saving
    the instance object currently.

    Make the instance object update the 'keypairs' field when saving the
    instance object.

    Conflicts:
            nova/tests/unit/fake_instance.py
            nova/tests/unit/objects/test_instance.py

    NOTE(stephenfin): Conflicts in 'fake_instance.py' are due to change
    If7f48933db10fcca3b9a05e1e978dfc51f6dabd0 ("Claim resources in resource
    tracker"), which is related to the vPMEM work and shouldn't be
    backported, while the conflicts in 'test_instance.py' are due to change
    Ic89352a9900515484bffe961475feb1cefc6b2a9 ("Remove
    'instance_update_at_top', 'instance_destroy_at_top'") which removed some
    cells v1 tests but shouldn't be removed here where cells v1 is
    technically still a thing.

    Change-Id: I8a2726b39d0444de8c35480024078a97430f5d0c
    Closes-Bug: #1843708
    Co-authored-by: Stephen Finucane <email address hidden>
    (cherry picked from commit 086796021b189c3ac64805ed8f6bde833906d284)
    (cherry picked from commit aed86ee5d6289edf1baf9fe0b2a9e509031fdd25)
    (cherry picked from commit b971dc82cb524fe86284c95ec671e2bad1c2874f)