Make the externally connectable browser test clobber all of the builtins,

chrome/renderer/resources/extensions/content_setting.js

 // Copyright (c) 2012 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 binding for the contentSettings API.
 
 var sendRequest = require('sendRequest').sendRequest;
 var validate = require('schemaUtils').validate;
 
 function extendSchema(schema) {
-  var extendedSchema = schema.slice();
+  var extendedSchema = $Array.slice(schema);
   extendedSchema.unshift({'type': 'string'});
   return extendedSchema;
 }
 
 function ContentSetting(contentType, settingSchema) {
   this.get = function(details, callback) {
     var getSchema = this.functionSchemas.get.definition.parameters;
     validate([details, callback], getSchema);
     return sendRequest('contentSettings.get',
                        [contentType, details, callback],
                        extendSchema(getSchema));
   };
   this.set = function(details, callback) {
-    var setSchema = this.functionSchemas.set.definition.parameters.slice();
+    var setSchema = $Array.slice(
+        this.functionSchemas.set.definition.parameters);
     setSchema[0].properties.setting = settingSchema;
     validate([details, callback], setSchema);
     return sendRequest('contentSettings.set',
                        [contentType, details, callback],
                        extendSchema(setSchema));
   };
   this.clear = function(details, callback) {
     var clearSchema = this.functionSchemas.clear.definition.parameters;
     validate([details, callback], clearSchema);
     return sendRequest('contentSettings.clear',
                        [contentType, details, callback],
                        extendSchema(clearSchema));
   };
   this.getResourceIdentifiers = function(callback) {
     var schema =
         this.functionSchemas.getResourceIdentifiers.definition.parameters;
     validate([callback], schema);
     return sendRequest(
         'contentSettings.getResourceIdentifiers',
         [contentType, callback],
         extendSchema(schema));
   };
 }
 
 exports.ContentSetting = ContentSetting;