CSSCharsetRuleImpl* clone = new CSSCharsetRuleImpl(*this);
CSSImportRuleImpl* clone = new CSSImportRuleImpl(*this);
CSSCharsetRuleImpl::Clone(nsICSSRule*& aClone) const{  CSSCharsetRuleImpl* clone = new CSSCharsetRuleImpl(*this);  if (clone) {    return CallQueryInterface(clone, &aClone);  }  aClone = nsnull;  return NS_ERROR_OUT_OF_MEMORY;}