WebString canonicalizeSelector(WebString webSelector, WebSelectorType restriction) { CSSSelectorList selectorList = CSSParser::parseSelector(strictCSSParserContext(), nullptr, webSelector); if (restriction == WebSelectorTypeCompound) { for (const CSSSelector* selector = selectorList.first(); selector; selector = selectorList.next(*selector)) { if (!selector->isCompound()) return WebString(); } } return selectorList.selectorsText(); }