Move special app access code into its own package.

... for easier code coverage. Two dummy activities are created in
place, which immediately finish themselves upon launch.

Bug: 152055112
Test: rm -r packages/apps/PermissionController/src/com/android/permissioncontroller/role/ui/specialappaccess/
Test: rm packages/apps/PermissionController/src/com/android/permissioncontroller/role/ui/auto/AutoSpecialAppAccess*
Test: then build and test
Change-Id: I162bb4dafc3b9c026bc8db6f46ce64ce0e83157a