Minimal skeleton for location time zone providers

Minimal skeleton for location time zone providers. Most behavior has
been stripped and more detail will be added later.

Test: atest services/tests/servicestests/src/android/location/timezone/LocationTimeZoneEventTest.java
Test: services/tests/servicestests/src/com/android/internal/location/timezone/LocationTimeZoneProviderRequestTest.java
Change-Id: I64102df0970e6cfbcc07c9377b226c8663a29a74