[dom] Document.defaultCharset (#58)

IE, Blink and WebKit all have `Document.defaultCharset` and the usage in Chrome isn't low enough that it can be trivially removed:
https://www.chromestatus.com/metrics/feature/timeline/popularity/428

Can we specify this? The concept itself is already referenced as "an implementation-defined or user-specified default character encoding" in HTML's [determining the character encoding](https://html.spec.whatwg.org/#determining-the-character-encoding), and assuming the side effects of that are observable, this wouldn't actually expose new information about users.

This should probably be blocked on [Document.charset](https://www.w3.org/Bugs/Public/show_bug.cgi?id=27436).

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/dom/issues/58