Comment 2 for bug 1696221

Reviewed: https://review.openstack.org/471486
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=c3d466dd4d9739844404fdd9c4170c4a8284a4aa
Submitter: Jenkins
Branch: master

commit c3d466dd4d9739844404fdd9c4170c4a8284a4aa
Author: Matt Riedemann <email address hidden>
Date: Tue Jun 6 17:28:42 2017 -0400

    Avoid unnecessary lazy-loads in mutated_migration_context

    If the instance isn't being migrated and has the
    migration_context attribute set to None, like during a rebuild
    operation, we should detect that and exit early rather
    than lazy-load several fields (numa_topology, pci_requests,
    and pci_devices - all separately) and then just not use/need
    them.

    Change-Id: I071ab575bfd80db029d542cebfdb3d4e34227881
    Closes-Bug: #1696221