Auto merge of #25367 - pshaughn:ce_undefined_is, r=jdm

apply is: to Document.createElement even when name isn't registered yet

The "is" option to Document.createElement should be respected even when the name hasn't been registered yet, in which case the name gets looked up again at the time the element should be upgraded. This change does that.
I'm now seeing a few test timeouts that aren't in the metadata, but I suspect they're slowness on my local configuration and not actual breakage.

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- [X] These changes fix #25009 fix #24997 and fix #24998

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