Issue 1727 - Fix WebSocket constructor without second argument in Chrome 47

include.preload.js

Index: include.preload.js
===================================================================
--- a/include.preload.js
+++ b/include.preload.js
@@ -379,6 +379,7 @@
     // As far as possible we must track everything we use that could be
     // sabotaged by the website later in order to circumvent us.
     var RealWebSocket = WebSocket;
+    var bindWebSocket = Function.prototype.bind.apply.bind(Function.prototype.bind, RealWebSocket);
     var closeWebSocket = Function.prototype.call.bind(RealWebSocket.prototype.close);
     var addEventListener = document.addEventListener.bind(document);
     var removeEventListener = document.removeEventListener.bind(document);
@@ -400,13 +401,14 @@
       }));
     }
 
-    WebSocket = function WrappedWebSocket(url, protocols)
+    WebSocket = function WrappedWebSocket()
     {
-      // Throw correct exceptions if the constructor is used improperly.
-      if (!(this instanceof WrappedWebSocket)) return RealWebSocket();
-      if (arguments.length < 1) return new RealWebSocket();
+      var args = [this];
+      for (var i = 0; i < arguments.length; i++)
+        args[i + 1] = arguments[i];
 
-      var websocket = new RealWebSocket(url, protocols);
+      var ctor = bindWebSocket(args);
+      var websocket = this instanceof WrappedWebSocket ? new ctor : ctor();
 
       checkRequest(websocket.url, function(blocked)
       {