Fix weird case of multi cell icons

 - Don't auto-inflate cell icons
 - Move callback to better time (shouldn't get callbacks before
   setSubs)
 - Fix accidental callback in MobileSignalController constructor
 - Fix subscription listener to run on the right thread to avoid
   the thread issue allowing this bug

Bug: 21504138
Change-Id: Ie1adf8eb05e1042245eead5354b29b314a2e0aae