[css-properties-values-api] Consume a component name presumably shouldn't allow CSS wide keywords, but it does.

[emilio]

https://drafts.css-houdini.org/css-properties-values-api-1/#consume-syntax-component:

When you hit a name-start code point:

If the stream starts with an identifier, reconsume the current input code point from stream then consume a name from stream, and set component’s name to the returned <ident-token>’s value. Otherwise return failure.

Per #259, I assume that it should match <custom-ident>. Blink does throw for this:

CSS.registerProperty({ name: "--bar", syntax: "inherit", inherits: false, })

cc @andruud @tabatkins

[emilio]

Relatedly, are there WPT tests for this?

[andruud]

In my defense, my original PR handled this [1], but it got lost in Tab's pass over the text. (Thankfully section 3.1 still says "Any sequence which starts an identifier, can be consumed as a name, and matches the <custom-ident> production", so at least there's that. We should still fix "Consume a syntax component", of course).

I don't remember right now if there's a test for this particular case. I think so, as I remember us having expectations.txt for something like this due to missing revert support. I'll check tomorrow and add one if it's missing.

Related PR : #861

[andruud]

@emilio Yes, it's covered by WPT. (Not revert, though. I was thinking of another test).