Settings: last gesture disabled doesn't retain value

[stakes]

If the user switches off all three "show controls" gestures, the last one switched off doesn't actually disable that gesture - instead, even though the switch shows it as disabled, it stays enabled.

The bug is when you switch off all three gestures, then turn one back on that's different from the last one you turned off, you actually end up with two gestures enabled instead of the single gesture reflected in the UI.