[w3c/webcomponents] A custom element should be marked as "failed" if a constructor returns a wrong object (#561)

Step 10 of [upgrading an element](https://html.spec.whatwg.org/multipage/scripting.html#concept-upgrade-an-element):
> If `SameValue(constructResult.[[value]], element)` is false, then throw an "`InvalidStateError`" `DOMException` and terminate these steps.
should also set the custom element state to "failed" so that we don't try to upgrade it again.

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