Enable builtin Mojo JS modules in layout tests

content/public/common/bindings_policy.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_COMMON_BINDINGS_POLICY_H_
 #define CONTENT_PUBLIC_COMMON_BINDINGS_POLICY_H_
 
 namespace content {
 
 // This enum specifies flag values for the types of JavaScript bindings exposed
 // to renderers.
 enum BindingsPolicy {
   // HTML-based UI bindings that allows the JS content to send JSON-encoded
   // data back to the browser process.
   BINDINGS_POLICY_WEB_UI = 1 << 0,
   // DOM automation bindings that allows the JS content to send JSON-encoded
   // data back to automation in the parent process.  (By default this isn't
   // allowed unless the app has been started up with the --dom-automation
   // switch.)
   BINDINGS_POLICY_DOM_AUTOMATION = 1 << 1,
   // Bindings that allows the JS content to retrieve a variety of internal
   // metrics. (By default this isn't allowed unless the app has been started up
   // with the --enable-stats-collection-bindings switch.)
   BINDINGS_POLICY_STATS_COLLECTION = 1 << 2,
+  // Bindings that allows the JS content to access Mojo system API and
+  // ServiceRegistry modules. The system API modules are defined in
+  // //mojo/public/js and provide the ability to create Mojo primitives such as
+  // message and data pipes. The ServiceRegistry module (see
+  // //content/renderer/mojo/service_registry_js_wrapper.h) in turn allows these
+  // Mojo primitives to be used to connect to named services exposed either by
+  // the browser or testing code. These bindings should not be exposed to
+  // normal web contents and are intended only for use with WebUI and layout
+  // tests.
+  BINDINGS_POLICY_MOJO = 1 << 3,
 
 };
 
 }
 
 #endif  // CONTENT_PUBLIC_COMMON_BINDINGS_POLICY_H_