There are 6 different situations which are now more explicitly covered to
ensure we handle them correctly:
1. Radio button (non-adaptive, single group only)
Selected -> Do nothing.
Unselected -> Replace override with selected track.
2. Check box (non-adaptive, but multi-group allowed)
Selected -> Remove track (and override). If last one, set isDisabled flag.
Unselected -> Replace override with selected track.
3. Check box (adaptive allowed, single or multi group)
Selected -> Remove track. If last, remove override and maybe set isDisabled.
Unselected -> Add track to override.
PiperOrigin-RevId: 236668642
36060e36cb