[dom] Fix some references around Document interface. (#108)

https://dom.spec.whatwg.org/#concept-document-url
base URL(a `URL`) and URL (a `URL`) << both `URL` inside () refers to URL in DOM, should not be directed to URL specification (https://url.spec.whatwg.org/#concept-url)?

https://dom.spec.whatwg.org/#dom-document-origin
Origin has wrong reference to Unicode serialization (should be #unicode-serialisation-of-an-origin). But this is a result of inconsistencies how some specs using terms, "serialization" vs "serialisation", ect., which form is correct, or more preferred? Just look dependencies from URL (https://html.spec.whatwg.org/multipage/infrastructure.html#concept-url-serialiser) and check how exactly this term was defined in URL spec.

And I have one quick question, what is the fast way to detect XML document or HTML document, if both of them will have the same Document interface? Internal type (https://dom.spec.whatwg.org/#concept-document-type) it's not exposed, so we should somehow analize `Document.contentType` by using regex?



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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/dom/issues/108