Switch from using unconfined_domain() to permissive_or_unconfined().
For user builds, or builds with FORCE_PERMISSIVE_TO_UNCONFINED=true,
this is a no-op. For userdebug / eng builds, this will allow us to
collect denials from /proc/last_kmsg.

Change-Id: I41e1a206b2a3b0eee34539bfebfc5deee9e18a42