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
@@ -406,7 +406,11 @@
       if (!(this instanceof WrappedWebSocket)) return RealWebSocket();
       if (arguments.length < 1) return new RealWebSocket();
 
-      var websocket = new RealWebSocket(url, protocols);
+      var websocket;
+      if (arguments.length == 1)
+        websocket = new RealWebSocket(url);
+      else
+        websocket = new RealWebSocket(url, protocols);

[Wladimir Palant, 2016/08/15 12:33:24]

Why make assumptions about the arguments in the first place? What if a third
parameter is added to the spec?

  var websocket = Object.create(RealWebSocket.prototype);
  RealWebSocket.apply(websocket, arguments);

[Wladimir Palant, 2016/08/15 12:45:36]

This will also allow dropping protocols parameter from the function signature -
then WebSocket.length will match the real thing.

[Wladimir Palant, 2016/08/15 13:01:24]

Never mind, calling RealWebSocket.apply() won't work no matter what you pass in
- detecting function call vs. new there doesn't work by checking this pointer.
So avoiding assumptions about parameters here requires spread operator which
sadly isn't supported before Chrome 46 or Safari 7.1, not worth it.

[Sebastian Noack, 2016/08/15 13:06:10]

See patchset #2 (and the related discussin) for a compatible way to pass
variable arguments.

 
       checkRequest(websocket.url, function(blocked)
       {