Though it seems the right thing to do at this stage, there is no plan to retire the Coupe des Mousquetaires, the trophy that goes to the winner of the men’s singles title at the French Open. Rafael Nadal has all but taken permanent possession of it, hoisting it high and biting down on its handle for the 11th time after defeating Dominic Thiem, 6-4, 6-3, 6-2, in the final on Sunday. But the French are, in a sense, retiring the historic stadium in which Nadal has established his historic dominance. Almost immediately after Thiem’s last return had flown long, the attendants in the tournament’s longstanding press room inside the Philippe Chatrier Court were distributing hard hats and colored markers to reporters and others for their demolition party. Much of the Chatrier Court, the main showplace at Roland Garros, will be demolished and rebuilt in the next 10 months to prepare for the installation of a retractable roof by 2020.