BUG/MINOR: stream: Be sure to have a listener to increment its counters

In process_stream(), when a client or a server abort is handled, the
corresponding listener's counter is incremented. But, we must be sure to have a
listener attached to the session. This bug was introduced by the commit
cff0f739e51.

Thanks to Fred to reporting me the bug.

No need to backport this patch, except if commit cff0f739e51 is backported.
1 file changed