Case C-396/17: Judgment of the Court (First Chamber) of 8 May 2019 (request for a preliminary ruling from the Bundesverwaltungsgericht — Austria) — Martin Leitner v Landespolizeidirektion Tirol (Reference for a preliminary ruling — Social policy — Prohibition of all discrimination on grounds of age — Directive 2000/78/EC — Exclusion of professional experience acquired before the age of 18 — New system of remuneration and advancement — Maintaining a difference in treatment — Right to an effective remedy — Article 47 of the Charter of Fundamental Rights of the European Union — Justifications)