Support enhanced call blocking function

- Add settings about whether to accept or block an incoming call
from unidentified numbers by configuring the setting for each reason
(unregistered/private/pay phone/unknown).
- Show a notification when making an emergency call.

Bug: 28189985
Test: Manual
Merged-In: I134a60675c512d12fd6c235c9cf95e506fcc7b85
Change-Id: I134a60675c512d12fd6c235c9cf95e506fcc7b85
(cherry picked from commit c18a4320)