AdapterService: getSystemService before initNative

Use static import to simplify requireNonNull
Use a common method to have a Null check at init and not a crash
later on

Bug: 292141273
Bug: 291815510
Test: atest AdapterServiceTest
Test: atest AdapterServiceRestartTest
Test: atest AdapterServiceFactoryResetTest
Change-Id: I3dc5f697259e5e50a390fe95ba264315e518e251