Ensure payload type is properly checked when comparing against cached events.

(closes issue #16607)
Reported by: ddv2005
Patches:
      event.patch uploaded by ddv2005 (license 769)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@240411 65c4cc65-6c06-0410-ace0-fbb531ad65f3