web: Polyfill document.embeds to return ruffle-embeds too

[danielhjacobs]

No description provided.

[kjarosh]

Can we add a polyfill test for it?

[danielhjacobs]

Done

[evilpie]

This breaks documen.embeds == document.embeds and probably other invariants.

[danielhjacobs]

This breaks documen.embeds == document.embeds and probably other invariants.

Fixed in the latest commit

[kjarosh]

LGTM, but would be great if someone else (that knows more about polyfilling) would also take a look at this

[kjarosh]

I guess I have one more question: why doesn't it refer back to embeds for unknown keys?

Let's say that a website uses another extension (called foo) that makes some embeds work, and suppose it works similarly to Ruffle, changing embed to foo-embed. foo will also have to polyfill Document.embeds because of the same reasons, but by using the current approach those two polyfills will conflict with each other.

If I were to write this polyfill, I would assume that Document.embeds contains all non-Ruffle embeds, and then refer to it for length and unknown keys, at the same time making sure I don't polyfill it for the second time. Doesn't it make sense?