Updateability: Resolve dependency to android/internal/util/StateMachine

Copying IState, State and StateMachine class, and StateMachine test.
Modify the test code to use AndroidJUnit4, same as other BT tests.
All classes are marked hidden

Bug:146075686
Test: Build, test listening, talking, headset controlling on music,
video, audio, and mixing situation. Make atest StateMachineTest fail and
successful
Change-Id: I226fb7e73d5d0462050a5f30cf2a06518aa1c193