[content shell] add a getPropertyDescriptor trap to the test runner

content/shell/webkit_test_runner.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.
 
 var testRunner = testRunner || {};
 var accessibilityController = accessibilityController || {};
 var gamepadController = gamepadController || {};
 var eventSender = eventSender || {};
 var textInputController = textInputController || {};
 
 (function() {
   native function GetWorkerThreadCount();
   native function NotifyDone();
   native function OverridePreference();
   native function SetDumpAsText();
   native function SetDumpChildFramesAsText();
   native function SetPrinting();
   native function SetShouldStayOnPageAfterHandlingBeforeUnload();
   native function SetWaitUntilDone();
 
   native function NotImplemented();
 
   var DefaultHandler = function(name) {
     var handler = {
       get: function(receiver, property) {
         NotImplemented(name, property);
         return function() {}
+      },
+      getPropertyDescriptor: function(property) {
+        NotImplemented(name, property);
+        return undefined;
       }
     }
     return Proxy.create(handler);
   }
 
   var TestRunner = function() {
     Object.defineProperty(this,
                           "workerThreadCount",
                           {value: GetWorkerThreadCount});
     Object.defineProperty(this,
@@ skipping 23 matching lines @@
   gamepadController = new GamepadController();
 
   var EventSender = function() {}
   EventSender.prototype = DefaultHandler("eventSender");
   eventSender = new EventSender();
 
   var TextInputController = function() {}
   TextInputController.prototype = DefaultHandler("textInputController");
   textInputController = new TextInputController();
 })();