Use an enum for ChromeVox queue mode.

chrome/browser/resources/chromeos/chromevox/chromevox/injected/ui/widget.js

 // Copyright 2014 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.
 
 /**
  * @fileoverview Base class for all ChromeVox widgets.
  *
  * Widgets are keyboard driven and modal mediums for ChromeVox to expose
  * additional features such as lists, interactive search, or grids.
  */
@@ skipping 98 matching lines @@
   window.removeEventListener('keypress', this.onKeyPress, true);
   window.removeEventListener('keydown', this.onKeyDown, true);
   cvox.ChromeVox.stickyOverride = null;
 
   cvox.ChromeVox.earcons.playEarcon(cvox.AbstractEarcons.OBJECT_CLOSE);
   if (!opt_noSync) {
     this.initialNode = this.initialNode.nodeType == 1 ?
         this.initialNode : this.initialNode.parentNode;
     cvox.ApiImplementation.syncToNode(this.initialNode,
                                       true,
-                                      cvox.AbstractTts.QUEUE_MODE_QUEUE);
+                                      cvox.QueueMode.QUEUE);
   }
 
   this.active = false;
 };
 
 
 /**
  * Toggle between showing and hiding.
  */
 cvox.Widget.prototype.toggle = function() {
@@ skipping 56 matching lines @@
  */
 cvox.Widget.prototype.onKeyPress = function(evt) {
   return false;
 };
 /**
  * @return {boolean} True if any widget is currently active.
  */
 cvox.Widget.isActive = function() {
   return (cvox.Widget.ref_ && cvox.Widget.ref_.isActive()) || false;
 };