311 and The Offspring have announced a co-headlining tour. Gym Class Heroes will serve as support. Tour Dates: Jul. 25 – Mountain View, CA @ Shoreline Amphitheatre Jul. 27 – Salt Lake City, UT @ USANA Amphitheatre Jul. 28 – Las Vegas, NV @ Downtown Las Vegas Events Center Jul. 29 – Chula Vista, CA…