Port Mojo's sample_service.cc to JavaScript

mojo/public/bindings/js/test/run_js_tests.cc

 // Copyright 2013 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.
 
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "gin/modules/module_registry.h"
 #include "gin/test/file_runner.h"
 #include "gin/test/gtest.h"
 #include "mojo/public/bindings/js/core.h"
@@ skipping 27 matching lines @@
 
 // TODO(abarth): Should we autogenerate these stubs from GYP?
 TEST(JSTest, core) {
   RunTest("core_unittests.js");
 }
 
 TEST(JSTest, codec) {
   RunTest("codec_unittests.js");
 }
 
+TEST(JSTest, sample_test) {
+  base::FilePath path;
+  PathService::Get(base::DIR_SOURCE_ROOT, &path);
+  path = path.AppendASCII("mojo")
+             .AppendASCII("public")
+             .AppendASCII("bindings")
+             .AppendASCII("sample")
+             .AppendASCII("sample_test.js");
+  TestRunnerDelegate delegate;
+  gin::RunTestFromFile(path, &delegate);
+}
+
 }  // namespace
 }  // namespace js
 }  // namespace mojo