Enemy Shaco killed drag but showed up weird

its in the title lol. Enemy killed dragon but showed up as game_anouncement_OnKillDragon_Unknown_chat. I'm on a Macbook Pro (Retina, 15-inch, Early 2013) Processor 2.4 GHz Intel Core i7 Memory 8 GB 1600 MHz DDR3 Graphics NVIDIA GeForce GT 650M 1024 MB Running OS X El Capitan