Update Native Client Authors to be Chromium Authors for the code moved from the

ppapi/native_client/tests/ppapi_test_example/ppapi_test_example.js

-// Copyright (c) 2011 The Native Client Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
 function setupTests(tester, plugin) {
   // TODO(tester): replace with your tests.
 
   // Below are sample test cases demonstrating postMessage as the test
   // driving mechanism.
 
   tester.addAsyncTest('Example::Simple', function(status) {
@@ skipping 20 matching lines @@
       } else {
         status.assertEqual(message.data, 'Callback');
         status.pass();
       }
     });
 
     plugin.addEventListener("message", messageListener, false);
     plugin.postMessage("TestCallback");
   });
 }