The Strokes and Nancy Pelosi walk into the same hotel. It sounds like it could be a setup for a joke, but it was the situation the New York rockers found themselves in “Last Nite” as singer Julian Casablancas explained to the crowd Wednesday night at United Center. It was likely just one of the many random crossed paths in Chicago this week as celebrities and dignitaries converge for the opening of the Obama Presidential Center and others go abo…