Default permissions for carrier apps.

Provide the current list of carrier apps to PackageManager when we are
queried for them as part of granting default permissions. Trigger an
evaluation of default permissions whenever we are enabling a new
carrier app due to a change in SIM state (e.g. new carrier privilege
rules).

Bug: 21696731
Change-Id: I3d6d61712acb554878edeb5ee172887da16ef851