Aggregate filter does not decorate events that it generates

#1

Due to the noError variable, an aggregate filter will only decorate an event (implementing common options like add_tag) for events that pass through it. Events that it generates (timeouts, final flush) are not decorated. Is that a bug or a feature?

One can work around it by modifying the map prior to it being flushed, or adding the tag in the timeout_code.