Visual refresh of allocation profile page

runtime/bin/vmservice/client/lib/src/elements/collapsible_content.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 collapsible_content_element;
-
-import 'dart:html';
-import 'package:polymer/polymer.dart';
-import 'observatory_element.dart';
-
-/// An element which conditionally displays its children elements.
-@CustomTag('collapsible-content')
-class CollapsibleContentElement extends ObservatoryElement {
-  static const String _openIconClass = 'glyphicon glyphicon-chevron-down';
-  static const String _closeIconClass = 'glyphicon glyphicon-chevron-up';
-
-  @observable String iconClass = _openIconClass;
-  @observable String displayValue = 'none';
-
-  bool _collapsed = true;
-  bool get collapsed => _collapsed;
-  set collapsed(bool r) {
-    _collapsed = r;
-    _refresh();
-  }
-
-  CollapsibleContentElement.created() : super.created();
-
-  void enteredView() {
-    super.enteredView();
-    _refresh();
-  }
-
-  void toggleDisplay(Event e, var detail, Node target) {
-    collapsed = !collapsed;
-    _refresh();
-  }
-
-
-
-  void _refresh() {
-    if (_collapsed) {
-      iconClass = _openIconClass;
-      displayValue = 'none';
-    } else {
-      iconClass = _closeIconClass;
-      displayValue = 'block';
-    }
-  }
-}