Suricata

Following this fix: https://github.com/OISF/suricata/pull/4211/commits/d4bc46038133a26ac0010ef64c865746f95814c7,
file_data base64 mail attachment content inspection started working (see #2395)
on the sample pcap here: https://redmine.openinfosecfoundation.org/attachments/1560
when this single relevant example rule was present: https://redmine.openinfosecfoundation.org/attachments/1748

The problem is that, when a second content-matching rule is also present, as in: https://redmine.openinfosecfoundation.org/attachments/1793,
the file_data rule no longer fires (both rules should generate alerts on the sample pcap file)!

Opening new bug since
1. I don't know whether this is the same underlying root cause as #2395 itself, and
2. my redmine account apparently doesn't have the power to re-open a closed bug :)