Coldplay is always one of the hottest concerts of the season, but this time around the British superstars have managed to be even hotter by tapping gay-favorite Swedish star Robyn to open. And before both of them, the British “symphonic rock band” Wolf Gang. That’s a lot of show for the money. Sunday, July 8, and Monday, July 9, at the Verizon Center, 601 F St. NW. Tickets are $49.50 to $110. Call 202-628-3200 or visit verizoncenter.com.