Add bind(), recvFrom(), sendTo() for UDP socket.

chrome/renderer/resources/extensions/experimental.socket_custom_bindings.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Custom bindings for the experimental.socket API.
 
   var experimentalSocketNatives = requireNative('experimental_socket');
   var GetNextSocketEventId = experimentalSocketNatives.GetNextSocketEventId;
 
   var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
   var sendRequest = require('sendRequest').sendRequest;
   var lazyBG = requireNative('lazy_background_page');
 
   chromeHidden.registerCustomHook('experimental.socket', function(api) {
       var apiFunctions = api.apiFunctions;
 
       apiFunctions.setHandleRequest('create', function() {
           var args = arguments;
-          if (args.length > 3 && args[3] && args[3].onEvent) {
+          if (args.length > 1 && args[1] && args[1].onEvent) {
             var id = GetNextSocketEventId();
-            args[3].srcId = id;
-            chromeHidden.socket.handlers[id] = args[3].onEvent;
+            args[1].srcId = id;
+            chromeHidden.socket.handlers[id] = args[1].onEvent;
 
             // Keep the page alive until the event finishes.
             // Balanced in eventHandler.
             lazyBG.IncrementKeepaliveCount();
           }
           sendRequest(this.name, args, this.definition.parameters);
           return id;
         });
 
       // Set up events.
@@ skipping 22 matching lines @@
               break;
             }
             if (event.isFinalEvent) {
               delete chromeHidden.socket.handlers[event.srcId];
               // Balanced in 'create' handler.
               lazyBG.DecrementKeepaliveCount();
             }
           }
         });
     });