Don't update state after stop bluetooth tethering

After using ConnectivityManager.stopTethering(), TetheringSettings may
update state before PanService set mTetherOn to false. This makes the
toggle button checked again and user need click it twice to disable it.

Bug: 111578971
Test: on/off bluetooth tethering from settings UI
Change-Id: I6873d762d2a290080d844b7a44e54f4bd532347e
1 file changed