When a resize is confirmed the instance does not belong to the source
compute any more. In the past the scheduler instance info is only
updated by the _sync_scheduler_instance_info periodic. This caused that
server boots with anti-affinity did not consider the source host.
But now at the end of the confirm_resize call the compute also updates
the scheduler about the move.
Conflicts:
nova/tests/unit/compute/test_compute_mgr.py
due to Ib50b6b02208f5bd2972de8a6f8f685c19745514c and
Ia6d8a7909081b0b856bd7e290e234af7e42a2b38 are missing from
stable/stein
Change-Id: Ic50e72e289b56ac54720ad0b719ceeb32487b8c8
Closes-Bug: #1869050
(cherry picked from commit 738110db74)
(cherry picked from commit e8b3927c92)
(cherry picked from commit e34b375a61)