Replace "context object" with "this" once IDL is updated

[marcoscaceres]

DOM defines a generally useful "context object" definition in its infrastructure section. I'm planning to use it in Payment Request, because we have a bunch of "Let foo be the Foo on which this method was called." ... but "Let foo be the context object." is way nicer.

Anyway, could we move "context object" to the Infra spec, as it seems generally useful?

[annevk]

The plan is for IDL to expose "this" to specification algorithms. See https://www.w3.org/Bugs/Public/show_bug.cgi?id=27301. I thought we had a newer issue for that, but I cannot find it. @tobie?

[tobie]

I think there's just an open PR: ~~~whatwg/webidl#258~~~ whatwg/webidl#495.

[annevk]

That's slots, not "this", no?

[tobie]

Right, it's part of the slots proposal, but that what the wrong link. There you go: whatwg/webidl#495.