Further status logic tweaks

Change the SettingsUI logic slightly: All other things being equal, pick
the "worst" location dependency status to show. Some renaming and
annotations for clarity.

Also fixes the mocking behavior in the tests around resources, which
were accidentally using the real strings and therefore dependent on real
resource string values. Tests are made more explicit.

Bug: 266921482
Test: atest tests/robotests/src/com/android/settings/datetime/LocationProviderStatusPreferenceControllerTest.java
Change-Id: Ifd96c543dad692884be23bf94e3f1294eed291d5