BOOST extension: battery died and "on for rotations" block is stuck highlighted

[ericrosenbaum]

Just noting this bug for discussion- we should discuss whether it is severe enough to warrant a fix:

The BOOST battery died while a "turn for rotations" block was running. The “on for rotations” block was stuck highlighted after the disconnection. The highlight can be cleared using the stop button.

[knandersen]

ah, that's an interesting edge case! It makes sense that the block gets stuck, since it's waiting to hear back from a hub that is no longer available.

One way of solving this could be to make sure that all BoostMotor-instances in the Boost.motors-array have their state cleared as part of the deinitialization in the Boost.disconnect-callback? since there's a regular check against the hub in Boost._pingDevice that should be a way of making sure those blocks can't get stuck.