Comment 7 for bug 1560119

Reviewed: https://review.openstack.org/349750
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=eba4586ef3db648bdda9cf0ffeb76398f0a761ea
Submitter: Jenkins
Branch: stable/mitaka

commit eba4586ef3db648bdda9cf0ffeb76398f0a761ea
Author: Goutham Pacha Ravi <email address hidden>
Date: Mon Mar 21 13:28:16 2016 -0400

    Fix force-delete on snapshot resource

    When using snapshot-delete API, if the share driver
    logs an exception, the status of the snapshot is set
    to 'error_deleting'. If an administrator wants to remove
    this snapshot, he/she would expect to use the
    snapshot-force-delete API. However, if the share
    driver still cannot delete the resource, it will remain
    in 'error_deleting' state; leaving the administrator
    with no choice but to resort to making changes to
    the snapshot record in Manila's database.

    Propagate the force flag to the share manager and log
    driver exceptions, while ignoring them to obliterate
    the snapshot on Manila's database if the delete
    operation is forced.

    Also fix data being sent in create/delete snapshot
    driver interfaces and refactor corresponding unit tests.

    Change-Id: Ic2494e1f9eb9104f96ef3a50f12d0f304735ee4f
    Closes-Bug: #1560119
    (cherry picked from commit 35648819aa00afe2cdd7ebba63f42def8c43e971)