Updated charted DEP to 0.4.X

packages/charted/lib/selection/transition.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
  */
 library charted.selection.transition;
 
-import "dart:html" show Element, document;
+import "dart:html" show Element;
 import "package:charted/core/timer.dart";
 import "package:charted/selection/selection.dart";
 import "package:charted/core/interpolators.dart";
 
 part 'src/transition_impl.dart';
 
 typedef Interpolator AttrTweenCallback(datum, int ei, String attr);
 typedef Interpolator StyleTweenCallback(datum, int ei, String style);
 
 /**
@@ skipping 141 matching lines @@
   /**
    * Removes all selected elements from the DOM at the end of the transition.
    * If any of the selected elements have another transition scheduled when
    * this transition ends, said elements will not be removed.
    */
   void remove();
 
   /** Factory method to create an instance of the default implementation */
   factory Transition(Selection selection) => new _TransitionImpl(selection);
 }