Turn on Polymer TodoMVC tests on Dart buildbots

pkg/polymer/test/run_all.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * This is a helper for run.sh. We try to run all of the Dart code in one
  * instance of the Dart VM to reduce warm-up time.
  */
 library run_impl;
 
@@ skipping 33 matching lines @@
   addGroup('transform/all_phases_test.dart', all_phases_test.main);
 
   endToEndTests('data/unit/', 'data/out');
 
   // Note: if you're adding more render test suites, make sure to update run.sh
   // as well for convenient baseline diff/updating.
 
   // TODO(jmesserly): figure out why this fails in content_shell but works in
   // Dartium and Firefox when using the ShadowDOM polyfill.
   exampleTest('../example/component/news', ['--no-shadowdom']..addAll(args));
-
-  exampleTest('../../../samples/third_party/todomvc');
 }
 
 void exampleTest(String path, [List<String> args]) {
   renderTests(path, '$path/test', '$path/test/expected', '$path/test/out',
       arguments: args);
 }
 
 void cssCompileMangleTest(String path, String pattern,
     [bool deleteDirectory = true]) {
   renderTests(path, path, '$path/expected', '$path/out',
@@ skipping 11 matching lines @@
       arguments: args, pattern: pattern, deleteDir: deleteDirectory);
 }
 
 void cssCompileShadowDOMTest(String path, String pattern,
     [bool deleteDirectory = true]) {
   var args = ['--no-css'];
   renderTests(path, path, '$path/expected', '$path/out',
       arguments: args, pattern: pattern,
       deleteDir: deleteDirectory);
 }