[breaking] Ensure that webSocketProxyError also receives the error …

…to be consistent with `proxyError` events.

lib/node-http-proxy/http-proxy.js

@@ -680,7 +680,7 @@ HttpProxy.prototype.proxyWebSocketRequest = function (req, socket, head, buffer)
       socket.destroy();
     });
 
-    self.emit('webSocketProxyError', req, socket, head);
+    self.emit('webSocketProxyError', err, req, socket, head);
   }
 
   //