Improve Code object support in service and observatory

runtime/bin/vmservice/client/lib/src/observatory/isolate_manager.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.
 
 part of observatory;
 
 /// Collection of isolates which are running in the VM. Updated
 class IsolateManager extends Observable {
   ObservatoryApplication _application;
   ObservatoryApplication get application => _application;
 
   @observable final Map<String, Isolate> isolates =
       toObservable(new Map<String, Isolate>());
 
-  static bool _foundIsolateInMembers(int id, List<Map> members) {
+  static bool _foundIsolateInMembers(String id, List<Map> members) {
     return members.any((E) => E['id'] == id);
   }
 
   void _responseInterceptor() {
     _application.requestManager.responses.forEach((response) {
       if (response['type'] == 'IsolateList') {
         _updateIsolates(response['members']);
       }
     });
   }
 
   Isolate getIsolate(String id) {
     Isolate isolate = isolates[id];
-    if (isolate == null) {
-      isolate = new Isolate(id, '');
-      isolates[id] = isolate;
-    }
     return isolate;
   }
 
   void _updateIsolates(List<Map> members) {
     // Find dead isolates.
     var deadIsolates = [];
     isolates.forEach((k, v) {
       if (!_foundIsolateInMembers(k, members)) {
         deadIsolates.add(k);
       }
     });
     // Remove them.
     deadIsolates.forEach((k) {
       isolates.remove(k);
     });
     // Add new isolates.
     members.forEach((k) {
       var id = k['id'];
       var name = k['name'];
       if (isolates[id] == null) {
         var isolate = new Isolate(id, name);
         isolates[id] = isolate;
       } else {
         isolates[id].name = name;
       }
     });
   }
 }