[WIP] feat(ext/css): implement CSSOM

[lucacasonato]

Very much WIP! Just testing around.

The extent to which it works is that running

const sheet = new CSSStyleSheet();
sheet.insertRule("body { background-color: currentColor; }");
console.log(sheet);
const rule = sheet.cssRules.item(0);
console.log(rule);

logs

CSSStyleSheet { cssRules: CSSRuleList { length: 1 }, disabled: false }
CSSStyleRule { selectorText: "body" }

Closes #13898

[deckchairlabs]

Would this mean potentially/eventually importing css with assert?

import sheet from './styles.css' assert { type: 'css' }
console.log(sheet)

[lucacasonato]

@deckchairlabs Yup!

[deckchairlabs]

@deckchairlabs Yup!

Amazing!

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. Thank you for your contributions.

[timreichen]

Is this PR supposed to be closed?