[webidl] Add [[PlatformBrand]] internal slot to all platform objects (#97)

The [[PlatformBrand]] internal slot would be a List (in the ECMAScript sense) of strings. One string per interface on the interface chain of the object. So e.g., Text would have "Text, "CharacterData", "Node", "EventTarget".

This would allow us to be more specific what we mean with instances of something and would also clear up a lot of language in IDL I think.

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Reply to this email directly or view it on GitHub:
https://github.com/heycam/webidl/issues/97