Adapt Document fullscreen events to new structure

[queengooborg]

This PR updates the fullscreenchange and fullscreenerror events of the Document API to conform to the new style. Part of work for #14578.

Content PR: mdn/content#12926

[sideshowbarker]

So I see this entirely deletes onfullscreenerror and onfullscreenchange and doesn’t add anything. That’s intended, right?

[queengooborg]

So I see this entirely deletes onfullscreenerror and onfullscreenchange and doesn’t add anything. That’s intended, right?

Yes, this intended as the existing _event properties cover all the data already!

[Elchi3]

So I see this entirely deletes onfullscreenerror and onfullscreenchange and doesn’t add anything. That’s intended, right?

Yes, this intended as the existing _event properties cover all the data already!

That's correct. However, we usually also add the spec_urls from the on-entries to the _event entries making it clear it's now the entry for both. See https://github.com/mdn/browser-compat-data/blob/main/docs/data-guidelines.md#dom-events-eventname_event for the full guideline.

[queengooborg]

@Elchi3 The reason I hadn't updated the spec_url is because it is the same URL for both members!

[Elchi3]

Thanks @queengooborg, that makes sense then :)