Add "show additional permissions" screen to app permissions for TV.

This also cleans up some code:
1) Factor out isTelevision into Utils.isTelevision() and call
   it where we were previously inlining that code
2) Make AppPermissionsFragment work better with config changes
   and screen rotation changes (the extra screen wasn't working
   at all with such changes)

b/22045242

Change-Id: I937eaa67f19f44b5e1a76a58e3fdd799ae36e73b