Properly parse out underscored parameters

(cherry picked from commit 298fc8523c80baa23edb819efa91864a80538c0a)

Bug: 60947
Change-Id: Ib1cc601b436b791ebfa91c08a634c5e77de409c2
(bug 60906) Truncate content before storing event into DB

Because the event_extra column is limited in size, so we don't want
to store too much ;)

(cherry picked from c3127a5ae37d3966e2aef9ae00d60923f8f3d57c)

Bug: 60906
Change-Id: I0ee10904caaaadecf43c8c5440f901e6888809bb
(bug 56811) reply field for replying to tangents has wrong name in it

(cherry picked from ba7dfb483438f78ad487c97084fdb65b296ae006)

Bug: 56811
Change-Id: Id4843140889d4da645f02308bc47e2a1fd06abfe