EventQueue should be terminated only by its owner

Both `Service.notifyConnectionListeners` and `Folder.notifyConnectionListeners` are calling `EventQueue.terminateQueue()` if `type` is `ConnectionEvent.CLOSED` . However, if `mail.event.scope` is set to 'application' or 'session' this can cause to some later events to be lost without being processed.

This problem should be fixed to allow queue termination only when object that is processing event owns `EventQueue`.

Start with Service.notifyConnectionListeners and Folder.notifyConnectionListeners, then trace how EventQueue.terminateQueue() determines ownership. Reproduce the CLOSED-event behavior with application- or session-scoped mail.event.scope, and verify that only the owning object terminates the queue and later events are still processed.

Written by the indexing model from the issue text.