Web updates

Web IDL fc5da8f167dd

Correct requirement to define Global properties on the object itself (#639) The specification required defining the operations and attributes for the Global interface itself as well as its inherited interfaces on the object itself. This is not implemented in Gecko, Chrome or WebKit: none of these engines defines, for example, the `addEventListener` method on the window object. I suspect this text was meant to refer to mixin interfaces rather than inherited interfaces, but these are already covered by a catch-all statement.