A variety of cleanups to bring our samples up-to-date.

samples/webcomponents/list_map.dart

-// Copyright (c) 2011, 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.
-
-/** 
- * ListMap class so that we have a dictionary usable with non-hashable keys.
- * Note: this class does NOT yet have full Map functionality 
- */
-class ListMap<K, V> {
-
-  List<_Pair<K, V>> _list;
-
-  ListMap() 
-    : _list = new List<_Pair<K, V>>() { }
-
-  void operator []=(K key, V value) {
-    _list.add(new _Pair<K,V>(key, value));
-  }
-
-  V operator [](K key) {
-    for (var pair in _list) {
-      if (pair._key == key)
-        return pair._value;
-    }
-    return null;
-  }
-}
-
-class _Pair<K, V> {
-  K _key;
-  V _value;
-
-  _Pair(this._key, this._value);
-}