Delete polymer from the Dart repo

pkg/polymer/test/property_change_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.property_change_test;
-
-import 'dart:async';
-import 'package:polymer/polymer.dart';
-import 'package:unittest/unittest.dart';
-import 'package:unittest/html_config.dart';
-
-// Dart note: this is a tad different from the JS code. We don't support putting
-// expandos on Dart objects and then observing them. On the other hand, we want
-// to make sure that superclass observers are correctly detected.
-
-final _zonk = new Completer();
-final _bar = new Completer();
-
-@reflectable
-class XBase extends PolymerElement {
-  @observable String zonk = '';
-
-  XBase.created() : super.created();
-
-  zonkChanged() {
-    expect(zonk, 'zonk', reason: 'change calls *Changed on superclass');
-    _zonk.complete();
-  }
-}
-
-@CustomTag('x-test')
-class XTest extends XBase {
-  @observable String bar = '';
-
-  XTest.created() : super.created();
-
-  ready() {
-    bar = 'bar';
-    new Future(() { zonk = 'zonk'; });
-  }
-
-  barChanged() {
-    expect(bar, 'bar', reason: 'change in ready calls *Changed');
-    _bar.complete();
-  }
-}
-
-main() => initPolymer().run(() {
-  useHtmlConfiguration();
-
-  setUp(() => Polymer.onReady);
-
-  test('bar change detected', () => _bar.future);
-  test('zonk change detected', () => _zonk.future);
-});