Joined Cases C-435/15 and C-666/15: Judgment of the Court (Ninth Chamber) of 22 March 2017 (requests for a preliminary ruling from the Finanzgericht Hamburg — Germany, Rechtbank Noord-Holland — Netherlands) — GROFA GmbH v Hauptzollamt Hannover (C-435/15), X, GoPro Coöperatief UA v Inspecteur van de Belastingdienst/Douane kantoor Rotterdam Rijnmond (C-666/15) (References for a preliminary ruling — Common Customs Tariff — Tariff headings — Classification of goods — Video Camera Recorders — Combined Nomenclature — Subheadings 8525 80 30, 8525 80 91 and 8525 80 99 — Explanatory notes — Interpretation — Implementing Regulations (EU) Nos 1249/2011 and 876/2014 — Interpretation — Validity)