Wire up an api to darken screen for accessibility

chrome/renderer/resources/extensions/automation/automation_node.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.
 
 var AutomationEvent = require('automationEvent').AutomationEvent;
 var automationInternal =
     require('binding').Binding.create('automationInternal').generate();
 var exceptionHandler = require('uncaught_exception_handler');
 var IsInteractPermitted =
     requireNative('automationInternal').IsInteractPermitted;
@@ skipping 402 matching lines @@
   },
 
   stopDuckingMedia: function() {
     this.performAction_('stopDuckingMedia');
   },
 
   suspendMedia: function() {
     this.performAction_('suspendMedia');
   },
 
+  toggleDarkenScreen: function(toggle) {
+    this.performAction_('toggleDarkenScreen', { darkenScreen: toggle });
+  },
+
   domQuerySelector: function(selector, callback) {
     if (!this.rootImpl)
       callback();
     automationInternal.querySelector(
       { treeID: this.rootImpl.treeID,
         automationNodeID: this.id,
         selector: selector },
       $Function.bind(this.domQuerySelectorCallback_, this, callback));
   },
 
@@ skipping 677 matching lines @@
       'htmlAttributes',
       'nameFrom',
   ]),
 });
 
 function AutomationRootNode() {
   privates(AutomationRootNode).constructPrivate(this, arguments);
 }
 utils.expose(AutomationRootNode, AutomationRootNodeImpl, {
   superclass: AutomationNode,
+  functions: [
+    'toggleDarkenScreen'
+  ],
   readonly: [
     'chromeChannel',
     'docTitle',
     'docUrl',
     'docLoaded',
     'docLoadingProgress',
     'anchorObject',
     'anchorOffset',
     'anchorAffinity',
     'focusObject',
     'focusOffset',
     'focusAffinity',
   ],
 });
 
 utils.defineProperty(AutomationRootNode, 'get', function(treeID) {
   return AutomationRootNodeImpl.get(treeID);
 });
 
 utils.defineProperty(AutomationRootNode, 'getOrCreate', function(treeID) {
   return AutomationRootNodeImpl.getOrCreate(treeID);
 });
 
 utils.defineProperty(AutomationRootNode, 'destroy', function(treeID) {
   AutomationRootNodeImpl.destroy(treeID);
 });
 
 exports.$set('AutomationNode', AutomationNode);
 exports.$set('AutomationRootNode', AutomationRootNode);