https://github.com/whatwg/webidl/pull/1465 updates QuotaExceededError from a specific DOMException name, to a subclass of DOMException.
Deno could either:
Do the minimal thing, and remove "QuotaExceededError" from the DOMException names table, so that (new DOMException("message", "QuotaExceededError")).code === 0; or
Do the minimal thing, plus also implement QuotaExceededError.