* RFC 7232 § 2.2 for semantics.
* - etag: Return an entity-tag representing the state of all resources involved
* in the request. Quotes must be included. See RFC 7232 § 2.3 for semantics.
- * @return string|boolean|null As described above, or null if no value is available.
+ * @return string|bool|null As described above, or null if no value is available.
*/
public function getConditionalRequestData( $condition ) {
return null;