Comment 3 for bug 1739995

Reviewed: https://review.openstack.org/530964
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=78cd77edef1a08f0472b8df0409adebb9b12e865
Submitter: Zuul
Branch: stable/pike

commit 78cd77edef1a08f0472b8df0409adebb9b12e865
Author: TommyLike <email address hidden>
Date: Mon Dec 25 09:19:20 2017 +0800

    Validate volume status again when snapshot created

    In a multitask environment, the volume can be deleted
    after the snapshot record is created. Add the validation
    right after the creation to avoid undeletable snapshot.

    Closes-Bug: #1739995

    Change-Id: Icbe86473243871996483fdc96c079b8861bac2e5
    (cherry picked from commit 7ccfb2c8d94824321d4bfca7266c5d72674c061f)
    Conflicts:
     cinder/tests/unit/api/v3/test_snapshots.py
     cinder/tests/unit/volume/test_volume.py