On Friday, the emo-nostalgia When We Were Young festival was supposed to kick off in Las Vegas, but it was not to be. The fest’s organizers had to cancel the first day of When We Were Young because of a “high wind warning” — truly one of the strangest reasons that I’ve ever seen for a live-show cancellation. Fortunately, Warped Tour veteran Katy Perry happened to be playing Las Vegas that night, as part of her Play residency at Resorts World. A large number of When We Were Young “orphans” apparently ended up at Perry’s show instead, and she was only too happy to welcome them.