Fix transient Next button in confirm screen on orientation change

During orientation change, input method service could have stale
input editor info. The portrait mode password entry allows fullscreen
UI and it is made visible for a glimpse of second during the change.
This CL adds the flagNoFullscreen to portrait mode password entry
so that the transient switch to fullscreen UI does not happen.

Bug:21073469
Change-Id: Ie9d21e46f88ad0395afb8750ab5d19e938685b89