Defer null permission check to default device context

Consider null permission as a non device aware permission and defer all
its checks to the default context.
Tricky to test since almost all permission check APIs require non null
permission. The only place where the permission can be null is from the
internals of AppOpsService where the entry points are mostly private.
Should open for testing some method, not feasible for the current
release.

Bug: 443664119
Test: atest android.permission.cts.DevicePermissionsTest
Flag: EXEMPT BUGFIX
Change-Id: I8a3609f559d8a14fecc3f21af299c4b78a0bae36