Explaining that a variable named "$username" contains a "username" is
not helpful. One have to read this comment first to understand that it
does not add anything to what's already obvious from the variable name
and the type.
Change-Id: I9a43866498d0c94422caf16233f502320a8e36c9
Followup to I639b9d9906d3ff37021cb9b5ed3cb401354b5bd9
* Remove deprecated formatter
* Log a warning and fail gracefully
when an event type does not support
Echo presentation model.
Bug: T121612
Change-Id: Ic5712c4ce265b6faabce7a4028b4294fe3c73f18