Should reviver functions still get a context argument for non-primitive values?

[gibson042]

Source text access is restricted to primitive values per #10 (comment) , so there is currently no information to provide for non-primitive values:

JSON.parse("42", (key, val, context) => context) // => {source: "42"}
JSON.parse("{}", (key, val, context) => context) // => ???

Some possibilities:

1. Do not provide the argument at all.
2. Provide undefined.
3. Provide an object with no source property ({}).
4. Provide an object with source: undefined.

[gibson042]

I am in favor of the third option, always providing the object for consistency (and in particular to not break callbacks that attempt to destructure it) but omitting the source property.