Use mojo from the PDF extension instead of using an extension API.

extensions/test/data/mojo_private_unittest.js

-// Copyright 2015 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.
-
-'use strict';
-
-let mojoPrivate = require('mojoPrivate').binding;
-let test = require('test').binding;
-let unittestBindings = require('test_environment_specific_bindings');
-
-unittestBindings.exportTests([
-  function testDefine() {
-    mojoPrivate.define('testModule', [
-      'mojo/public/js/codec',
-    ], test.callbackPass(function(codec) {
-      test.assertEq('function', typeof codec.Message);
-    }));
-  },
-
-  function testDefineRegistersModule() {
-    mojoPrivate.define('testModule', ['dependency'],
-                       test.callbackPass(function(module) {
-      test.assertEq(12345, module.result);
-    }));
-    mojoPrivate.define('dependency', test.callbackPass(function() {
-      return {result: 12345};
-    }));
-  },
-
-  function testDefineModuleDoesNotExist() {
-    mojoPrivate.define('testModule', ['does not exist!'], test.fail);
-    test.succeed();
-  },
-
-  function testRequireAsync() {
-    mojoPrivate.requireAsync('mojo/public/js/codec').then(
-        test.callbackPass(function(codec) {
-          test.assertEq('function', typeof codec.Message);
-        }));
-  },
-
-  function testDefineAndRequire() {
-    mojoPrivate.define('testModule', ['dependency'],
-                       test.callbackPass(function(module) {
-      test.assertEq(12345, module.result);
-    }));
-    mojoPrivate.define('dependency', test.callbackPass(function() {
-      return {result: 12345};
-    }));
-    mojoPrivate.requireAsync('dependency').then(
-        test.callbackPass(),
-        test.fail);
-  }
-], test.runTests, exports);