Comment 7 for bug 1685340

Reviewed: https://review.openstack.org/480744
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=b296f1e2e6590262a6702fb49d175f761cb901e2
Submitter: Jenkins
Branch: stable/ocata

commit b296f1e2e6590262a6702fb49d175f761cb901e2
Author: Matt Riedemann <email address hidden>
Date: Thu Apr 27 14:44:52 2017 -0400

    Do not log live migration success when it actually failed

    During post live migration, if post live migration on destination
    fails, then we log a stacktrace but continue to perform cleanup
    on the source side. However, at the end of the _post_live_migration
    method it was logging that things were successful on the destination
    host, which they weren't, which is really confusing when you're trying
    to debug the failure and seeing this conflict in the logs.

    This patch simply sets a flag if we failed post live migration at
    the destination host so we don't log the success message later on
    the source host, plus tests to show the flag is set and checked.

    Change-Id: I16e70912a13c963031397e66a8553b2c199d50bd
    Closes-Bug: #1685340
    (cherry picked from commit 746e48efa32fd599817197ffd7ad434a35f96165)