Comment 26 for bug 1718512

Reviewed: https://review.openstack.org/560162
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=0d111f17c4e411a42beb6c80bc27e6455a71c48c
Submitter: Zuul
Branch: stable/ocata

commit 0d111f17c4e411a42beb6c80bc27e6455a71c48c
Author: Matt Riedemann <email address hidden>
Date: Wed Sep 20 14:24:44 2017 -0400

    Add regression test for persisted RequestSpec.retry from failed resize

    Commit 74ab427d4796d8a386f84a15cc49188c2a60f8f1 in Newton added
    code to persist changes to the RequestSpec during a resize since
    the flavor changes.

    That change inadvertantly also persisted any failed hosts during
    the resize that are stored in the RequestSpec.retry field during
    a reschedule.

    The problem is that later those persisted failed hosts are rejected
    by the RetryFilter, which can be confusing if an admin is trying
    to live migrate or evacate the instance to one of those specific
    hosts.

    This adds a functional regression test to show the failure, which
    will be fixed in a separate change that then modifies the assertions.

    NOTE(mriedem): There are two changes in this backport:

    1. The functional test needed to change slightly to disable the
       DiskFilter since 2fe96819c24eff5a9493a6559f3e8d5b4624a8c9 is
       not in Ocata.

    2. The test needs to use 'api_post' directly on the API client for
       the confirmResize call since the check_response_status kwarg
       wasn't in post_server_action until 8dd11ca1b34e1ed58b4 in Pike.

    Change-Id: Ib8a23db838b0bbf2cfb8123cf6aaa39d00ff0640
    Related-Bug: #1718512
    (cherry picked from commit 89448bea577b30c40ce39185d14fe14f9c61a0c2)
    (cherry picked from commit c2dc902e39eb345ebf674ad47422f1e72ec170e6)
    (cherry picked from commit 004e9acf99964ac78f85d3efbd0a04404bd9a3ef)