drained: handle missed "changing" events

[bobrippling]

Sometimes my watch will change (with drained active) past the threshold and not deactivate drained. On debugging, the interval isn't set, so we set it unconditionally to ensure we have a charge "watcher".

[thyttan]

Does this mean something is broken in the event handling somewhere?

I mean, why would we be missing to set the interval in the 'charging'-listener?

[thyttan]

We also discussed some weird event listener behavior on #4141.

Could this be something similar?

[bobrippling]

Good memory! I would initially say no, and that drained just starts too late but that can't be the case - drained is running when I plug my watch in to charge 🤔

It could well be something with the firmware, like #4141. I'll see if I can get more details

[thyttan]

@bobrippling I'm thinking of opening an issue re event handling on espruino/Espruino. Have you managed to understand the problem any more?

[bobrippling]

I'm afraid not - still at square one!

[stweedo]

There is one specific case i found with version 0.08 of drained where if it's started while the watch is charging, it will not deactivate when crossing the threshold until a new charging event happens by reconnecting the charger.