Case T-591/15: Judgment of the General Court of 13 December 2018 — Transavia Airlines v Commission (State aid — Airport and marketing services agreement — Agreement between the Chamber of Commerce and Industry of Pau-Béarn and Transavia — Decision declaring the aid to be incompatible with the internal market and ordering its recovery — Concept of State aid — Whether attributable to the State — Chamber of Commerce and Industry — Advantage — Private investor test — Recovery — Article 41 of the Charter of Fundamental Rights — Right of access to the file — Right to be heard)