Track live instance and allocation counts for classes

runtime/bin/vmservice/client/lib/src/observatory_elements/service_ref.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 service_ref_element;
 
 import 'package:polymer/polymer.dart';
 import 'observatory_element.dart';
 
 @CustomTag('service-ref')
 class ServiceRefElement extends ObservatoryElement {
   @published Map ref;
   @published bool internal = false;
   ServiceRefElement.created() : super.created();
 
   void refChanged(oldValue) {
     notifyPropertyChange(#url, "", url);
     notifyPropertyChange(#name, [], name);
+    notifyPropertyChange(#hoverText, "", hoverText);
   }
 
   String get url {
     if ((app != null) && (ref != null)) {
       return app.locationManager.currentIsolateRelativeLink(ref['id']);
     }
     return '';
   }
 
+  String get hoverText {
+    if (ref == null) {
+      return '';
+    }
+    // Return the VM name by default.
+    var name = ref['name'];
+    return name != null ? name : '';
+  }
+
   String get name {
     if (ref == null) {
       return '';
     }
     String name_key = internal ? 'name' : 'user_name';
     if (ref[name_key] != null) {
       return ref[name_key];
+    } else if (ref['name'] != null) {
+      return ref['name'];
     }
     return '';
   }
 }