Fix check for id attribute.
Fix check for id attribute.

togusafish/t-ashula-_-DOMPurify,kwangkim/DOMPurify,tdeekens/DOMPurify,neilj/DOMPurify,neilj/DOMPurify,tdeekens/DOMPurify,tdeekens/DOMPurify,neilj/DOMPurify,voku/DOMPurify,kwangkim/DOMPurify,Joris-van-der-Wel/DOMPurify,voku/DOMPurify,Joris-van-der-Wel/DOMPurify,Joris-van-der-Wel/DOMPurify,togusafish/t-ashula-_-DOMPurify