Revert of [Extensions] Finish freezing schema

extensions/renderer/resources/json_schema.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.
 
 // -----------------------------------------------------------------------------
 // NOTE: If you change this file you need to touch
 // extension_renderer_resources.grd to have your change take effect.
 // -----------------------------------------------------------------------------
 
 //==============================================================================
@@ skipping 312 matching lines @@
  * |errors| property, and returns a boolean indicating whether the instance
  * validates.
  */
 JSONSchemaValidator.prototype.validateEnum = function(instance, schema, path) {
   for (var i = 0; i < schema.enum.length; i++) {
     if (instance === enumToString(schema.enum[i]))
       return true;
   }
 
   this.addError(path, "invalidEnum",
-                [$Array.join($Array.map(schema.enum, enumToString), ", ")]);
+                [schema.enum.map(enumToString).join(", ")]);
   return false;
 };
 
 /**
  * Validates an instance against an object schema and populates the errors
  * property.
  */
 JSONSchemaValidator.prototype.validateObject =
     function(instance, schema, path) {
   if (schema.properties) {
@@ skipping 172 matching lines @@
 };
 
 /**
  * Resets errors to an empty list so you can call 'validate' again.
  */
 JSONSchemaValidator.prototype.resetErrors = function() {
   this.errors = [];
 };
 
 exports.$set('JSONSchemaValidator', JSONSchemaValidator);