Make ChromeVox Next a setting in options page.

chrome/browser/resources/chromeos/chromevox/cvox2/background/desktop_automation_handler.js

 // Copyright 2015 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 Handles automation from a desktop automation node.
  */
 
 goog.provide('DesktopAutomationHandler');
 
@@ skipping 80 matching lines @@
    */
   onEventDefault: function(evt) {
     var node = evt.target;
     if (!node)
       return;
 
     var prevRange = ChromeVoxState.instance.currentRange;
 
     ChromeVoxState.instance.setCurrentRange(cursors.Range.fromNode(node));
 
-    // Check to see if we've crossed roots. Continue if we've crossed roots or
-    // are not within web content.
-    if (node.root.role == RoleType.desktop ||
-        !prevRange ||
-        prevRange.start.node.root != node.root)
-      ChromeVoxState.instance.refreshMode(node.root);
-
     // Don't process nodes inside of web content if ChromeVox Next is inactive.
     if (node.root.role != RoleType.desktop &&
         ChromeVoxState.instance.mode === ChromeVoxMode.CLASSIC) {
       if (cvox.ChromeVox.isChromeOS)
         chrome.accessibilityPrivate.setFocusRing([]);
       return;
     }
 
     // Don't output if focused node hasn't changed.
     if (prevRange &&
@@ skipping 107 matching lines @@
 
     this.onEventDefault(
         new chrome.automation.AutomationEvent(EventType.focus, node));
   },
 
   /**
    * Provides all feedback once a load complete event fires.
    * @param {!AutomationEvent} evt
    */
   onLoadComplete: function(evt) {
-    ChromeVoxState.instance.refreshMode(evt.target);
-
     // Don't process nodes inside of web content if ChromeVox Next is inactive.
     if (evt.target.root.role != RoleType.desktop &&
         ChromeVoxState.instance.mode === ChromeVoxMode.CLASSIC)
       return;
 
     chrome.automation.getFocus(function(focus) {
       if (!focus || !AutomationUtil.isDescendantOf(focus, evt.target))
         return;
 
       // If initial focus was already placed on this page (e.g. if a user starts
@@ skipping 165 matching lines @@
   if (cvox.ChromeVox.isMac)
     return;
   chrome.automation.getDesktop(function(desktop) {
     global.desktopAutomationHandler = new DesktopAutomationHandler(desktop);
   });
 };
 
 DesktopAutomationHandler.init_();
 
 });  // goog.scope