Add support for retrieving image thumbnails as part of the accessibility tree.

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 349 matching lines @@
   },
 
   doDefault: function() {
     this.performAction_('doDefault');
   },
 
   focus: function() {
     this.performAction_('focus');
   },
 
+  getImageData: function(maxWidth, maxHeight) {
+    this.performAction_('getImageData',
+                        { maxWidth: maxWidth,
+                          maxHeight: maxHeight });
+  },
+
   makeVisible: function() {
     this.performAction_('makeVisible');
   },
 
   setSelection: function(startIndex, endIndex) {
     if (this.role == 'textField' || this.role == 'textBox') {
       this.performAction_('setSelection',
                           { focusNodeID: this.id,
                             anchorOffset: startIndex,
                             focusOffset: endIndex });
@@ skipping 270 matching lines @@
     'action',
     'ariaInvalidValue',
     'autoComplete',
     'containerLiveRelevant',
     'containerLiveStatus',
     'description',
     'display',
     'dropeffect',
     'help',
     'htmlTag',
+    'imageDataUrl',
     'language',
     'liveRelevant',
     'liveStatus',
     'name',
     'placeholder',
     'shortcut',
     'textInputType',
     'url',
     'value'];
 
@@ skipping 384 matching lines @@
 
 function AutomationNode() {
   privates(AutomationNode).constructPrivate(this, arguments);
 }
 utils.expose(AutomationNode, AutomationNodeImpl, {
   functions: [
     'doDefault',
     'find',
     'findAll',
     'focus',
+    'getImageData',
     'makeVisible',
     'matches',
     'setSelection',
     'setSequentialFocusNavigationStartingPoint',
     'showContextMenu',
     'addEventListener',
     'removeEventListener',
     'domQuerySelector',
     'toString',
     'boundsForRange',
@@ skipping 42 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);