Comment 2 for bug 1785776

Reviewed: https://review.openstack.org/589425
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=3311d579db2482c5d06cd4e245da57333b79a8db
Submitter: Zuul
Branch: master

commit 3311d579db2482c5d06cd4e245da57333b79a8db
Author: Balazs Gibizer <email address hidden>
Date: Tue Aug 7 12:57:47 2018 +0200

    Fix resize revert to use non-legacy alloc handling

    During the revert of resize or migrate nova tries to drop the
    allocation on the target host. But first it decides if the resize uses
    the new style allocation handling where the source host allocation is
    held by the migration. If not then the legacy double-up allocation
    handling is triggered.

    However the implementation tried to check if the migration holds
    allocation on the destination host and that is clearly wrong as migration
    only holds alloction on the source host.

    This patch now changes the check to simply assert if there is any
    allocation held by the migration.uuid.

    Change-Id: I41c10ca5caa01dda950dd17319889963850fed59
    Closes-Bug: #1785776