Comment 4 for bug 1712689

Reviewed: https://review.openstack.org/497237
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=df6ea0412f462815cf57560e96f33f4e2ff9d072
Submitter: Jenkins
Branch: stable/pike

commit df6ea0412f462815cf57560e96f33f4e2ff9d072
Author: Matt Riedemann <email address hidden>
Date: Wed Aug 23 17:27:05 2017 -0400

    How about not logging errors every time we shelve offload?

    The delete_allocation_for_instance method does not return
    anything and "if not None" is always True, so we're always
    logging an error when we shelve offload an instance, which
    is not the most fun thing in the world.

    This was probably caused by some confusion with how
    remove_provider_from_instance_allocation works which does
    return a boolean result.

    Change-Id: I30b716b0649f6d367ea747149da5c5f921ae19c5
    Closes-Bug: #1712689
    (cherry picked from commit e208cbb1f122b948af91a8d11c0f45dcec5bbc76)