So this has to do with the way Polymer does dirty checking
from within dom-repeat. Since the underlying array instance
identity was not changed, the dom-repeat would not trigger
and the reply dialog was not updated properly.
Additionally:
+ Guard against searching for a saved draft when discarding
one that hasn’t been saved.
+ Move _files to be a compute function.
Change-Id: Idc49f158cba7f908d50f163a6fdbd93fbe585462
861c4a255f