[Modify] Replace it

websocket-sharp/Server/HttpServer.cs

@@ -661,13 +661,8 @@ namespace WebSocketSharp.Server
 
       set {
         lock (_sync) {
-          string msg;
+          if (!canSet ())
-
-          if (!canSet (out msg)) {
-            _log.Warn (msg);
-
             return;
-          }
 
           _listener.UserCredentialsFinder = value;
         }