Update event logging schema for Echo to match schema at
http://meta.wikimedia.org/w/index.php?title=Schema%3AEcho&diff=5423520&oldid=5417976

Change-Id: I55e3d57126936519d1abbcaa50d7ae8965b84f64
Merge "Update event logging schema for Echo to match schema at http://meta.wikimedia.org/w/index.php?title=Schema%3AEcho&diff=5423520&oldid=5417976"