Revert 28422

runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/collapsible_content.dart

Index: runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/collapsible_content.dart
diff --git a/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/collapsible_content.dart b/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/collapsible_content.dart
deleted file mode 100644
index 5422447ff5e8ae0aa936fec356ca625b97a3befe..0000000000000000000000000000000000000000
--- a/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/collapsible_content.dart
+++ /dev/null
@@ -1,46 +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.
-
-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 get iconClass => __$iconClass; String __$iconClass = _openIconClass; set iconClass(String value) { __$iconClass = notifyPropertyChange(#iconClass, __$iconClass, value); }
-  @observable String get displayValue => __$displayValue; String __$displayValue = 'none'; set displayValue(String value) { __$displayValue = notifyPropertyChange(#displayValue, __$displayValue, value); }
-
-  bool _collapsed = true;
-  bool get collapsed => _collapsed;
-  set collapsed(bool r) {
-    _collapsed = r;
-    _refresh();
-  }
-
-  void toggleDisplay(Event e, var detail, Node target) {
-    collapsed = !collapsed;
-    _refresh();
-  }
-
-  void inserted() {
-    super.inserted();
-    _refresh();
-  }
-
-  void _refresh() {
-    if (_collapsed) {
-      iconClass = _openIconClass;
-      displayValue = 'none';
-    } else {
-      iconClass = _closeIconClass;
-      displayValue = 'block';
-    }
-  }
-}