select_destinations should send start/end notifications

[John Garbutt]

In the filter scheduler, schedule_run_instance sends notifications, but select_destinations does not.

This is inconsistent, and we should send start/end notifications from both code paths.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/116022

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/116022
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=926f94534da7b3cd868eb6495a2eaadd5faff6b9
Submitter: Jenkins
Branch: master

commit 926f94534da7b3cd868eb6495a2eaadd5faff6b9
Author: John Garbutt <email address hidden>
Date: Thu Aug 21 16:58:13 2014 +0100

    scheduler sends select_destinations notifications

    scheduler_run_instance sends start/end notifications so you can tell how
    long it takes for the scheduler to do its work.

    The new select_destinations does not send any such notifications.

    To make the new code patch more consistent with the notifications in the
    old code patch, this change adds in start/end notifications.

    The notification docs should be updated to reflect this change.

    DocImpact

    Closes-Bug: #1359835

    Change-Id: I9b3f6619823c57cbc21d714edd78527c0015b4f6