Updated charted DEP to 0.4.X

packages/charted/lib/charts/src/chart_config_impl.dart

 //
 // Copyright 2014 Google Inc. All rights reserved.
 //
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 //
 
 part of charted.charts;
 
@@ skipping 39 matching lines @@
     assert(values != null && values.isNotEmpty);
 
     _disposer.dispose();
     _series = values;
     notifyChange(const ChartConfigChangeRecord());
 
     // Monitor each series for changes on them
     values.forEach((item) {
       if (item is Observable) {
         _disposer.add(
-            item.changes
+            (item as Observable)
+                .changes
                 .listen((_) => notifyChange(const ChartConfigChangeRecord())),
             item);
       }
     });
 
     // Monitor series for changes.  When the list changes, update
     // subscriptions to ChartSeries changes.
     if (_series is ObservableList) {
       var observable = _series as ObservableList;
       _disposer.add(observable.listChanges.listen((records) {
@@ skipping 58 matching lines @@
   set isRTL(bool value) {
     if (_isRTL != value && value != null) {
       _isRTL = value;
       notifyChange(const ChartConfigChangeRecord());
     }
   }
 
   @override
   bool get isRTL => _isRTL;
 }