Use an enum for ChromeVox queue mode.

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.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 The entry point for all ChromeVox2 related code for the
  * background page.
  */
 
 goog.provide('cvox2.Background');
@@ skipping 167 matching lines @@
       return;
     var container = node;
     while (container && (container.role == 'inlineTextBox' ||
         container.role == 'staticText'))
       container = container.parent();
 
     var role = container ? container.role : node.role;
 
     var output =
         [node.attributes.name, node.attributes.value, role].join(', ');
-    cvox.ChromeVox.tts.speak(output, cvox.AbstractTts.QUEUE_MODE_FLUSH);
+    cvox.ChromeVox.tts.speak(output, cvox.QueueMode.FLUSH);
     cvox.ChromeVox.braille.write(cvox.NavBraille.fromText(output));
     chrome.accessibilityPrivate.setFocusRing([evt.target.location]);
 
     this.current_ = node;
   },
 
   /**
    * Provides all feedback once a load complete event fires.
    * @param {Object} evt
    */
@@ skipping 22 matching lines @@
   disableClassicChromeVox_: function(tabId) {
     chrome.tabs.executeScript(
           tabId,
           {'code': 'try { window.disableChromeVox(); } catch(e) { }\n',
            'allFrames': true});
   }
 };
 
 /** @type {cvox2.Background} */
 cvox2.global.backgroundObj = new cvox2.Background();