Fix AlarmManagerServiceTest and add some more tests

The tests were failing due to an NPE in SettingsProvider. Mocking the
content resolver to separate test code from internal details.
Added couple more tests.

Test: atest FrameworksMockingServicesTests:AlarmManagerServiceTest

Bug: 111454659
Change-Id: Ie9784a4645f4559254894a3904f0c156167d49c6
4 files changed