Don't load profile widgets until parent is unlocked.

Wait for parent user to be unlocked before attempting
to load widgets for a user.
Fixes issue with profile being unlocked and AppWidgetServiceImpl
thinking it has loaded parents widgets while locked and
therefore not seeing any widgets.

Bug: 27037962
Change-Id: Ice9c5e6e1dd062a622c5f984eeb3531de893f9be