Case C-638/16 PPU: Judgment of the Court (Grand Chamber) of 7 March 2017 (request for a preliminary ruling from the Conseil du Contentieux des Étrangers — Belgium) — X and X v État belge (Reference for a preliminary ruling — Regulation (EC) No 810/2009 — Article 25(1)(a) — Visa with limited territorial validity — Issuing of a visa on humanitarian grounds or because of international obligations — Concept of ‘international obligations’ — Charter of Fundamental Rights of the European Union — European Convention for the Protection of Human Rights and Fundamental Freedoms — Geneva Convention — Issuing of a visa where a risk of infringement of Article 4 and/or Article 18 of the Charter of Fundamental Rights is established — No obligation)