[Feature] Include class name that causes save game failure

[MajorCooke]

I'm trying to debug what's causing a failure to save a game, and right now the information present is simply not good enough. If we could include what class is trying to save and causing an issue, it'd help out immensely.

All it says is "Save failed. Attempt to save pointer to unhandled type NativeStruct".

It'd be improved if the game added "in class ".