Fix repeating apps on pause/resume

Preference list was getting duplicated on pausing and resuming the activity.

Pull the user info out of the preference list and make it a static header
so that it stays fixed. Can now remove all entries before re-adding.

Disable location by default and disable ability to change Unknown sources
 toggle.

Bug: 8685561
Bug: 8688400

Change-Id: I64ce728d5369e03ddaba562bcd66bb0720a037d2