Revert "fix nested bindings"

pkg/polymer/test/nested_binding_test.dart

-// Copyright (c) 2013, 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.
-
-library polymer.test.nested_binding_test;
-
-import 'dart:async';
-import 'dart:html';
-import 'dart:mirrors'; // import mirrors so we include String.length
-import 'package:polymer/polymer.dart';
-import 'package:unittest/unittest.dart';
-import 'package:unittest/html_config.dart';
-import 'package:unittest/matcher.dart';
-
-@CustomTag('my-test')
-class MyTest extends PolymerElement {
-  final List fruits = toObservable(['apples', 'oranges', 'pears']);
-
-  final _testDone = new Completer();
-
-  MyTest.created() : super.created();
-
-  _runTest(_) {
-    expect($['fruit'].text.trim(), 'Short name: [pears]');
-    _testDone.complete();
-  }
-
-  ready() {
-    onMutation($['fruit']).then(_runTest);
-  }
-
-}
-
-main() {
-  reflectClass(String); // use the mirrors import to suppress a warning.
-
-  initPolymer();
-  useHtmlConfiguration();
-
-  setUp(() => Polymer.onReady);
-
-  test('ready called', () => (query('my-test') as MyTest)._testDone.future);
-}