Add permission check on onKeyguardVisibilityChanged

Without this permission check any app can toggle the locked state of
keymaster once it has been unlocked for the first time.

Bug: 144285084
Test: Manually tested with debugger that the requred code paths are
      run.

Merged-In: Idb8a200dc2963e1085e9fddd0c565c5172465e65
Change-Id: Idb8a200dc2963e1085e9fddd0c565c5172465e65
(cherry picked from commit 21f452c3722ad7fa39c7d84c4723bcbb723ab164)
(cherry picked from commit aad9178b5784ee573cfe369afc9aff0171747263)
1 file changed