This CL adds the basics to set black, dark gray or light gray list
enforcement, rather than just black as before. It's not possible to
actually set the policy per-package yet.
PackageDexOptimizer still uses a single bit, for API checks on/off, rather
than the new enum. It assumes blacklist enforcement internally. This can
be improved in a follow up CL.
(cherry-picked from commit e52130ae4c)
Test: m
Test: Boot device
BUG: 73337509
Change-Id: Ieb4bd9cc439c6a5b8fb9424d8902d8b46aec309f
Merged-In: Idd73c9938592c5c4d67cfb9efefdffed0dd5f262
e3299533b5