Ticket #47581 - Winsync plugin segfault during incremental backoff
Bug description: Once WinSync backoff timer is set, even if the
protocol that the backoff timer belongs to is deleted by removing
the windows sync agreement, the timer is not deleted from the event
queue. Thus the timer is expired and backoff is called, it crashes
the server since the protocol handle is already freed, then.
Fix description: Make sure to delete the backoff timer when
1) a windows sync agreement is removed and the protocol is deleted, and
2) a new backoff timer set and there is already a backoff timer set up.
https://fedorahosted.org/389/ticket/47581
Reviewed by rmeggins (Thank you, Rich!!)
(cherry picked from commit d70e66b2157ce3ba40c5e1cb074c2d5c150ddc5b)
(cherry picked from commit 59846f7247bae47f8fbcfc808c4cb6e6e96e2dc9)
(cherry picked from commit be0e47009a44af34f8dc0dd38f1a1ae1a49c42ce)