1: startService -------stopService (this will call onDestroy)
2: bindService -------unbindService (this will call onDestroy)
3: startService---bindService----stopService (nothing happen, shoud call unbindService)
4: startService---bindService----unbundService --- stopService (this will call onDestroy)
5: startService---bindService----stopService-----unbindService (this will call onDestroy)
6: bindService---startService---stopService (nothing happen, shoud call unbindService)
7: bindService---startService---unbindService----stopService (this will call onDestroy)
7: bindService---startService----stopService---unbindService (this will call onDestroy)