The UTF-8 normalization for the URL attributes `languagecode`, `uselang`
and `setlang` are not needed.
Change-Id: Ib204629fb15e2578bba09be4c40d0210eb81dd77
* Use isRegistered() from the more narrow UserIdentity interface.
* More specific type hints.
* Remove comments that literally repeat the code.
Change-Id: Icd0eaf8236be41b258efcf81d581540d2448e9e3