Add the ChromeOS trybot to the CQ config.

infra/config/cq.cfg

@@ -12,6 +12,7 @@ verifiers {
       name: "tryserver.chromium.angle"
       builders { name: "linux_angle_rel_ng" }
       builders { name: "linux_angle_dbg_ng" }
+      builders { name: "linux_angle_chromeos_rel_ng" }
       builders { name: "mac_angle_rel_ng" }
       builders { name: "mac_angle_dbg_ng" }
       builders { name: "win_angle_rel_ng" }