Handle all RTCICEConnectionState values in ARDVideoCallViewController

BUG=

Review URL: https://codereview.webrtc.org/1318343005

Cr-Commit-Position: refs/heads/master@{#9839}
diff --git a/webrtc/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m b/webrtc/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
index a26068f..674c97b 100644
--- a/webrtc/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
+++ b/webrtc/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
@@ -172,6 +172,7 @@
     case RTCICEConnectionFailed:
     case RTCICEConnectionDisconnected:
     case RTCICEConnectionClosed:
+    case RTCICEConnectionMax:
       return nil;
   }
 }