Apparently when the device is idle long enough the system will clean
up the dialog view for the hotspot band preference. This will cause
restore state to fail once it decides to pause the activity. To avoid
this we should make sure the boxes are not null.
Test: robotest
Bug: 78445411
Change-Id: I2a82b01f894f62be6c5209c78faddc4089aa6301
This CL updates the preference for selecting the enabled tether bands
to allow individual selection of multiple bands instead of forcing
a single selection. Note that while this makes the UI theoretically
support new bands in the future, the wifi backend only supports
selecting a single band or all bands which this CL does not address.
Test: robotests
Bug: 73102003
Change-Id: Ib2d4a2834c5cd11875515d308f7b20bfc8471959
