Revert "[fix minor] Prevent crashes from attempting to remove listene…

…rs more than once when proxying websocket requests."

This reverts commit a681493.

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

@@ -472,8 +472,6 @@ HttpProxy.prototype.proxyWebSocketRequest = function (req, socket, head, buffer)
   // the appropriate events.
   //
   function onUpgrade (reverseProxy, proxySocket) {
-    var detached;
-
     if (!reverseProxy) {
       proxySocket.end();
       socket.end();
@@ -545,15 +543,12 @@ HttpProxy.prototype.proxyWebSocketRequest = function (req, socket, head, buffer)
     // from `reverseProxy` and `proxySocket`.
     //
     function detach() {
-      if (!detached) {
-        detached = true;
-        proxySocket.destroySoon();
-        proxySocket.removeListener('end', listeners.onIncomingClose);
-        proxySocket.removeListener('data', listeners.onIncoming);
-        reverseProxy.incoming.socket.destroySoon();
-        reverseProxy.incoming.socket.removeListener('end', listeners.onOutgoingClose);
-        reverseProxy.incoming.socket.removeListener('data', listeners.onOutgoing);
-      }
+      proxySocket.destroySoon();
+      proxySocket.removeListener('end', listeners.onIncomingClose);
+      proxySocket.removeListener('data', listeners.onIncoming);
+      reverseProxy.incoming.socket.destroySoon();
+      reverseProxy.incoming.socket.removeListener('end', listeners.onOutgoingClose);
+      reverseProxy.incoming.socket.removeListener('data', listeners.onOutgoing);
     }
 
    //