Joystick instance IDs have different types in events and methods

[17cupsofcoffee]

#955 changed all of the events' which fields to u32 (with some reasonable justification!). Some of those which values are joystick IDs. If you try to get those same IDs from the Joystick or GameController struct, you currently get given an i32.

It's a minor thing, as I can just cast the value, but it seems a little inconsistent. Should this conversion be handled under the hood, or is this the intended behaviour? If the former, I might submit a PR.

[Cobrand]

You are right, it's not intended behaviour. Negative values are returned when errors happen, but they should be converted to Err(...) in those cases, that's why it's safe to use u32 for valid JoystickIDs. So yeah that should be fixed, feel free to drop a PR!