Remove service.Class.children, and (mostly) as a side-effect sort the class hierarchy view.

runtime/bin/vmservice/observatory/lib/src/elements/class_tree.dart

 // Copyright (c) 2014, 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 class_tree_element;
 
 import 'observatory_element.dart';
 import 'dart:html';
 import 'package:logging/logging.dart';
 import 'package:observatory/app.dart';
 import 'package:observatory/service.dart';
 import 'package:polymer/polymer.dart';
 
 class ClassTreeRow extends TableTreeRow {
   @reflectable final Isolate isolate;
   @reflectable final Class cls;
   ClassTreeRow(this.isolate, this.cls, ClassTreeRow parent) : super(parent) {
     assert(isolate != null);
     assert(cls != null);
   }
 
   void onShow() {
     if (children.length > 0) {
       // Child rows already created.
       return;
     }
-    for (var subClass in cls.children) {
-      if (subClass.isPatch) {
+    for (var subclass in cls.subclasses) {
+      if (subclass.isPatch) {
         continue;
       }
-      var row = new ClassTreeRow(isolate, subClass, this);
+      var row = new ClassTreeRow(isolate, subclass, this);
       children.add(row);
     }
   }
 
   void onHide() {
   }
 
   bool hasChildren() {
-    return cls.children.length > 0;
+    return cls.subclasses.length > 0;
   }
 }
 
 
 @CustomTag('class-tree')
 class ClassTreeElement extends ObservatoryElement {
   @observable Isolate isolate;
 
   TableTree tree;
 
@@ skipping 55 matching lines @@
       try {
         // Subtract 1 to get 0 based indexing.
         tree.toggle(row.rowIndex - 1);
       }  catch (e, stackTrace) {
         Logger.root.warning('toggleExpanded', e, stackTrace);
       }
     }
   }
 
 }