sys user split: update createUser method

After the system user is split out, all users are more or less the same.
We combine the generic user and secondary user create method to reflect
this concept.  This also fixes the bug the newly created Primary user
from lock screen contains secondary user restrictions.

Bug: 19913735
Change-Id: I407a877c11346409bad85e00038f6cfd3d126da3
1 file changed