Handle naming for system uids running as secondary users

Allow naming such as u1_system, u2_radio, u2_media.
Forward and reverse mapping for the above.

(cherry-pick of c60a0027b1ef3bc4929d2023e7083fbce12fafe7.)

Change-Id: I46eeb23fee4f57b2907640570504123d3ce99985
1 file changed