The logging manager's Manager::TraverseRecord(), called when adding a
log filter to a stream, skipped any fields intoduced by a filter's
$ext_func when such fields weren't mentioned in a $include restriction
or mentioned in an $exclude restriction. This was inconsistent with
Manager::RecordToFilterVals, used when actually writing log entries,
which does include those values.
The result was that the record indices descent in Manager::RecordToFilterVals
expects to find only record values, when in fact only the record
provided by ext_func is present. This leads to type mismatches and
hard Zeek exits like this one:
1300475173.475401 fatal error in zeek/share/zeek//base/init-bare.zeek, line 4810: Val::CONVERTER (string/record) (zeek)
The fix makes ext_func's field additions decisive, meaning the
filter's include/exclude lists don't apply to it. If a user really
wants to override this, they can reset the filter's ext_func back to
our no-op default.
The included btest produces the above error when the fix is not present.
