People who hate surprises, rejoice! I have good news. You may now come downtown, park your car and enjoy dinner and a show at the Aronoff and a very nearby eatery. Jeff Ruby has opened a new place that is custom tailored for you — the Walnut Street Grill. There are no bad surprises here. Nothing unfamiliar. These are upscaled (ever so slightly) versions of dishes you’ll find in most familiar casual restaurants.