Comment 15 for bug 1499669

Reviewed: https://review.openstack.org/373518
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=2dd44db1b9cf4b789d8a083df6f97ae1fb5e22d5
Submitter: Jenkins
Branch: stable/newton

commit 2dd44db1b9cf4b789d8a083df6f97ae1fb5e22d5
Author: Steve Baker <email address hidden>
Date: Fri Sep 16 03:29:59 2016 +0000

    Legacy delete attempt thread cancel before stop

    The error messages 'Command Out of Sync' are due to the threads being
    stopped in the middle of the database operations. This happens in the
    legacy action when delete is requested during a stack create.

    We have the thread cancel message but that was not being used in this
    case. Thread cancel should provide a more graceful way of ensuring the
    stack is in a FAILED state before the delete is attempted.

    This changes does the following in the delete_stack service method for
    legace engine:
    - if the stack is still locked, send thread cancel message
    - in a subthread wait for the lock to be released, or until a
      timeout based on the 4 minute cancel grace period
    - if the stack is still locked, do a thread stop as before

    Closes-Bug: #1499669
    Closes-Bug: #1546431
    Closes-Bug: #1536451
    Change-Id: I4cd613681f07d295955c4d8a06505d72d83728a0
    (cherry picked from commit 3000f904080d8dcd841d913dcd2ae658fb526c1a)