Movie music has been part of symphonic pops concerts at least since the 1940s, but Henry Mancini, the famed composer of scores for such movies as The Pink Panther and Breakfast at Tiffany’s, took things even further beginning around the 1960s, when he led more than 50 performances of his most popular themes each year across the United States and beyond. But David Newman, who returns to conduct On the Waterfront after leading West Side Story, points to John Williams as the biggest catalyst in changing attitudes in the classical world about film music.