Merge "Add more comments to the file header to explain the state diagram"

 * m1 = TURN_HOT

 * m2 = Transition to HotOff when number of process wanting BT on is 0.

 *      POWER_STATE_CHANGED will make the transition.

 * Note:

 * The diagram above shows all the states and messages that trigger normal state changes.

 * The diagram above does not capture everything:

 *   The diagram does not capture following messages.

 *   - messages that do not trigger state changes

 *     For example, PER_PROCESS_TURN_ON received in BluetoothOn state

 *   - unhandled messages

 *     For example, USER_TURN_ON received in BluetoothOn state

 *   - timeout messages

 *   The diagram does not capture error conditions and state recoveries.

 *   - For example POWER_STATE_CHANGED received in BluetoothOn state

 */

final class BluetoothAdapterStateMachine extends StateMachine {

    private static final String TAG = "BluetoothAdapterStateMachine";