Throws if the value of :lang() pseudo-class is quoted

[asamuzaK]

According to the spec: The Language Pseudo-class: :lang()

Each language range in :lang() must be a valid CSS <ident> or <string>. (Thus language ranges containing asterisks, for example, must be either correctly escaped or quoted as strings, e.g. :lang(*-Latn) or :lang("*-Latn").)

CSSTree throws if language ranges are quoted.

import { parse } from 'css-tree';
const ast = parse(':lang("*-Latn")', { context: 'selectorList' });
// throws `SyntaxError: Identifier is expected`

It succeeds if they are escaped, e.g. :lang(\*-Latn).