Cleanup mojo-js tests.

mojo/public/js/interface_ptr_tests.js

 // Copyright 2016 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.
 
 define([
     "gin/test/expect",
     "mojo/public/js/bindings",
     "mojo/public/js/core",
     "mojo/public/interfaces/bindings/tests/math_calculator.mojom",
     "mojo/public/js/threading",
@@ skipping 140 matching lines @@
                                            pipe.handle1);
 
     var promise = calc.add(2).then(function(response) {
       expect(response.value).toBe(2);
       return Promise.resolve();
     });
 
     return promise;
   }
 });