extensions/emmet/src/updateImageSize.ts/findUrlToken
function findUrlToken(editor: TextEditor, node: Property, pos: Position): CssToken | undefined {
	const offset = editor.document.offsetAt(pos);
	for (let i = 0, il = (node as any).parsedValue.length, url; i < il; i++) {
		iterateCSSToken((node as any).parsedValue[i], (token: CssToken) => {
			if (token.type === 'url' && token.start <= offset && token.end >= offset) {
				url = token;
				return false;
			}
			return true;
		});

		if (url) {
			return url;
		}
	}
	return;
}