Media columnist David Carr, who wrote the Media Equation column for The New York Times and penned a memoir about his fight with drug addiction, collapsed at his office and died on Thursday. He was 58. Just hours before his death he had moderated a “Times Talks” conversation with Edward Snowden, director Laura Poitras and journalist Glenn Greenwald about the documentary “Citizenfour,” which chronicles Snowden’s leak of National Security Agency documents.