Expose media controls to 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 376 matching lines @@
   },
 
   setSequentialFocusNavigationStartingPoint: function() {
     this.performAction_('setSequentialFocusNavigationStartingPoint');
   },
 
   showContextMenu: function() {
     this.performAction_('showContextMenu');
   },
 
+  startDucking: function() {
+    this.performAction_('startDucking');
+  },
+
+  stopDucking: function() {
+    this.performAction_('stopDucking');
+  },
+
   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 661 matching lines @@
     'doDefault',
     'find',
     'findAll',
     'focus',
     'getImageData',
     'makeVisible',
     'matches',
     'setSelection',
     'setSequentialFocusNavigationStartingPoint',
     'showContextMenu',
+    'startDucking',
+    'stopDucking',
     'addEventListener',
     'removeEventListener',
     'domQuerySelector',
     'toString',
     'boundsForRange',
   ],
   readonly: $Array.concat(publicAttributes, [
       'parent',
       'firstChild',
       'lastChild',
@@ skipping 37 matching lines @@
 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);