public static void collectCompletionVariants(TagNameReference tagNameReference,
                                               Consumer<? super LookupElement> consumer) {
    PsiElement element = tagNameReference.getElement();
    if (element instanceof XmlTag) {
      if (!tagNameReference.isStartTagFlag()) {
        for (LookupElement variant : createClosingTagLookupElements((XmlTag)element, false, tagNameReference.getNameElement())) {
          consumer.consume(variant);
        }
      }
      else {
        XmlTag tag = (XmlTag) element;
        for(LookupElement variant: getTagNameVariants(tag, tag.getNamespacePrefix())) {
          consumer.consume(variant);
        }
      }
    }
  }
public static void collectCompletionVariants(TagNameReference tagNameReference,
                                               Consumer<? super LookupElement> consumer)