Removed @Deprecated SystemService callback methods that take a userId.

This is just a plain refactoring: the removed methods in the changed
classes were called by default by the new methods in the superclass
(SystemService).

Test: m
Test: atest NotificationManagerServiceTest BackupManagerServiceRoboTest

Fixes: 161943081

Exempt-From-Owner-Approval: refactoring without side-effects

Change-Id: Ifd8df592eb4494cc0922b7e0b2ff20187b8a8b3e