Initial GUI for VM service

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

Index: runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/message_viewer.dart
diff --git a/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/message_viewer.dart b/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/message_viewer.dart
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+// 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 message_viewer_element;
+
+import 'package:polymer/polymer.dart';
+import 'observatory_element.dart';
+
+@CustomTag('message-viewer')
+class MessageViewerElement extends ObservatoryElement {
+  Map _message;
+  @published Map get message => _message;
+
+  @published set message(Map m) {
+    _message = m;
+    notifyProperty(this, #messageType);
+    notifyProperty(this, #members);
+  }
+
+  String get messageType {
+    if (message == null || message['type'] == null) {
+      return 'Error';
+    }
+    return message['type'];
+  }
+
+  List<Map> get members {
+    if (message == null || message['members'] == null) {
+      return [];
+    }
+    return message['members'];
+  }
+}