Fix devices with primary physical storage.

Always assume the factory-reset default primary storage before parsing
storage settings.  Without this, we'd always default to picking
internal emulated storage during first boot or upgrade.

Bump version code to re-evaluate this for devices that default to
physical storage as primary.

Also restrict available move targets when storage is physical, since
we can't really translate between multi-user and non-multi-user aware
storage.

Bug: 20836019
Change-Id: I186ded1aa3dd9cea67497a4f53b0973031174ccd