[encoding] Signaling EOF in the streaming case is unspecified (or too unclear) (#12)

AFAICT, Gecko's `TextDecoder` doesn't handle EOF at all in the streaming mode. When I look at the spec, it's not clear to me how EOF is supposed to be signaled in the API. By passing `null` as the input to `decode()` maybe?

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/encoding/issues/12