Add human readable programmatic enum name/values to chrome.automation.

chrome/renderer/resources/extensions/automation_custom_bindings.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.
 
 // Custom bindings for the automation API.
 var AutomationNode = require('automationNode').AutomationNode;
 var AutomationTree = require('automationTree').AutomationTree;
 var automation = require('binding').Binding.create('automation');
 var automationInternal =
     require('binding').Binding.create('automationInternal').generate();
 var eventBindings = require('event_bindings');
 var Event = eventBindings.Event;
 var lastError = require('lastError');
+var schema =
+    requireNative('automationInternal').GetSchemaAdditions();
 
 // TODO(aboxhall): Look into using WeakMap
 var idToAutomationTree = {};
 var idToCallback = {};
 
 // TODO(dtseng): Move out to automation/automation_util.js or as a static member
 // of AutomationTree to keep this file clean.
 /*
  * Creates an id associated with a particular AutomationTree based upon a
  * renderer/renderer host pair's process and routing id.
@@ skipping 85 matching lines @@
       for (var i = 0; i < idToCallback[id].length; i++) {
         var callback = idToCallback[id][i];
         callback(targetTree);
       }
       delete idToCallback[id];
     }
   }
 });
 
 exports.binding = automation.generate();
+
+// Additional bindings adopted from Accessibility.
+exports.binding.EventType = schema.EventType;
+exports.binding.RoleType = schema.RoleType;
+exports.binding.StateType = schema.StateType;