Use ServiceConfigAccessor directly

Architectural change: Make ServiceConfigAccessor a direct dependency of
TimeZoneDetectorStrategyImpl.

Previously, TimeZoneDetectorInternalImpl and TimeZoneDetectorService
used ServiceConfigAccessor directly for reading / writing config, and
TimeZoneDetectorStrategyImpl read it via it's "Environment"
facade and relied on async updates to follow along.

Upcoming changes that are likely to add more information to the cached
status information that downstream components will be interested in
(i.e. will want to listen to). This extra information will be held by
TimeZoneDetectorStrategyImpl so it will be easier if it is (only)
TimeZoneDetectorStrategyImpl that manages the ServiceConfigAccessor of
the three.

The dependency on ServiceConfigAccessor is removed from the classes
higher in the stack (TimeZoneDetectorService /
TimeZoneDetectorInternalImpl), which now call through to the Strategy.
The ServiceConfigAccessor functionality has been removed from the
Environment, and TimeZoneDetectorStrategyImpl uses ServiceConfigAccessor
directly.

Now that the TimeZoneDetectorStrategyImpl is in the direct config read /
update flow for binder calls, some care has been taken to ensure the
cached ConfigurationInternal is kept up to date. Previously, the
TimeZoneDetectorStrategyImpl updates happened asynchronously.  There's
some complexity around caching / eventual consistency here that might be
detectable but should not have any impact on behavior.

Notes for people following along: We cannot assume that the only thing
affecting config / status happens via TimeZoneDetectorStrategyImpl:
Android's settings and device config are mutatable via all sorts of
routes (e.g. command line, backup&restore, random partner apps). This is
not likely to change. Therefore, the TimeZoneDetectorStrategyImpl still
listens for ServiceConfigAccessor updates, but will (now) only forward
them on if something changes Vs the last one it notified about.

This commit changes the time zone strategy code. A follow-up will make
an equivalent change for the time code at a later time for consistency.

Bug: 253015306
Test: atest services/tests/servicestests/src/com/android/server/timedetector/ services/tests/servicestests/src/com/android/server/timezonedetector/
Test: atest ./tests/tests/time/src/android/app/time/cts/
Change-Id: Ie3fe60a624be8a5bb3e161a3e88f0a257cd96c3d