Move observe to observe package

pkg/polymer/lib/observe_html.dart

Index: pkg/polymer/lib/observe_html.dart
diff --git a/pkg/polymer/lib/observe_html.dart b/pkg/polymer/lib/observe_html.dart
deleted file mode 100644
index 7280b0e4434d11b48d66045353b86721f1e26a99..0000000000000000000000000000000000000000
--- a/pkg/polymer/lib/observe_html.dart
+++ /dev/null
@@ -1,63 +0,0 @@
-// 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.
-
-// TODO(jmesserly): can we handle this more elegantly?
-// In general, it seems like we want a convenient way to take a Stream plus a
-// getter and convert this into an Observable.
-
-/** Helpers for exposing dart:html as observable data. */
-library polymer.observe_html;
-
-import 'dart:html';
-import 'package:observe/observe.dart';
-
-/** An observable version of [window.location.hash]. */
-final ObservableLocationHash windowLocation = new ObservableLocationHash._();
-
-class ObservableLocationHash extends ChangeNotifierBase {
-  ObservableLocationHash._() {
-    // listen on changes to #hash in the URL
-    // Note: listen on both popState and hashChange, because IE9 doesn't support
-    // history API. See http://dartbug.com/5483
-    // TODO(jmesserly): only listen to these if someone is listening to our
-    // changes.
-    window.onHashChange.listen(_notifyHashChange);
-    window.onPopState.listen(_notifyHashChange);
-  }
-
-  String get hash => window.location.hash;
-
-  /**
-   * Pushes a new URL state, similar to the affect of clicking a link.
-   * Has no effect if the [value] already equals [window.location.hash].
-   */
-  void set hash(String value) {
-    if (value == hash) return;
-
-    window.history.pushState(null, '', value);
-    _notifyHashChange(null);
-  }
-
-  void _notifyHashChange(_) {
-    notifyChange(new PropertyChangeRecord(const Symbol('hash')));
-  }
-}
-
-/** Add or remove CSS class [className] based on the [value]. */
-void updateCssClass(Element element, String className, bool value) {
-  if (value == true) {
-    element.classes.add(className);
-  } else {
-    element.classes.remove(className);
-  }
-}
-
-/** Bind a CSS class to the observable [object] and property [path]. */
-PathObserver bindCssClass(Element element, String className,
-    Observable object, String path) {
-
-  return new PathObserver(object, path)..bindSync((value) {
-    updateCssClass(element, className, value);
-  });
-}