Processing window activity user exit check

A configured processing window activity user exit does not provide a reason to keep the window open.

When this check begins, the following message is logged:
IZLPB094I: Start check: user exit - processing window {0}.
If the user exit returns at least one reason, the window will not be closed and the following message is logged in the system log:
IZLPB065I: Processing window {0} is late. User defined: [{1}].
When all checks have completed, the following message is logged:
IZLPB071I: Finished check: window close criteria - processing window {0}.

If an exception is encountered by any of these checks, an appropriate message is logged and the window is held open.