Remove legacy restart code

runtime/observatory/lib/src/service/object.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.
 
 part of service;
 
 // Some value smaller than the object ring, so requesting a large array
 // doesn't result in an expired ref because the elements lapped it in the
 // object ring.
 const int kDefaultFieldLimit = 100;
@@ skipping 835 matching lines @@
     });
   }
 
   void _dispatchEventToIsolate(ServiceEvent event) {
     var isolate = event.isolate;
     if (isolate != null) {
       isolate._onEvent(event);
     }
   }
 
-  Future restart() {
-    return invokeRpc('_restartVM', {});
-  }
-
   Future<Map> _fetchDirect({int count: kDefaultFieldLimit}) async {
     if (!loaded) {
       // The vm service relies on these events to keep the VM and
       // Isolate types up to date.
       try {
         await listenEventStream(kVMStream, _dispatchEventToIsolate);
         await listenEventStream(kIsolateStream, _dispatchEventToIsolate);
         await listenEventStream(kDebugStream, _dispatchEventToIsolate);
         await listenEventStream(_kGraphStream, _dispatchEventToIsolate);
       } on FakeVMRpcException catch (_) {
@@ skipping 3759 matching lines @@
     var v = list[i];
     if ((v is Map) && _isServiceMap(v)) {
       list[i] = owner.getFromMap(v);
     } else if (v is List) {
       _upgradeList(v, owner);
     } else if (v is Map) {
       _upgradeMap(v, owner);
     }
   }
 }