Should Record.prototype.__proto__ be null?

[littledan]

@ljharb proposed this in #71 (comment) . I'm splitting it off into a separate issue so we can give this proper discussion.

My intuition would either be that all Record wrappers have a null prototype, or it goes up to Object (I'm open to either of those); I don't quite understand the motivation for this intermediate position, but I don't see any big problems with it.

[littledan]

For the Stage 2 draft, as per #71 (comment) , the current plan is that Record.prototype will be null ("Plan A"). For Stage 3, we'll be making a final decision between that and another plan ("Plan B") where we would have a Record.prototype, and also open to discuss other ideas. If Record.prototype is not null, I'm fine with making Record.prototype.__proto__ null, for the reasons @ljharb suggested. I'm making this as "Stage 3" since it's dependent on that other decision that we're open to reconsidering until Stage 3.

[rricard]

Per the decision on #71, Records have null prototypes so there cannot be a __proto__ on it.