In this generator change, we introduce a new factory method for bound
LibWeb objects that takes a JS::Realm instead of Web::HTML::Window.
The two methods are allowed to co-exist at this point, but the option to
take an HTML::Window will be removed once all clases are converted to
the new API.
We also start using the new Bindings::ensure_web_[prototype/constructor]
helpers from the Bindings/Intrinsics class so that we can eventually
remove the helpers from Window.h for the same.
8407bf60c5