Add getClassList RPC

tests/standalone/vmservice/multiple_isolate_list_test.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 multiple_isolate_list_test;
-
-import 'test_helper.dart';
-import 'package:expect/expect.dart';
-
-class MultipleIsolateListTest extends VmServiceRequestHelper {
-  MultipleIsolateListTest(port) : super('http://127.0.0.1:$port/vm');
-
-  onRequestCompleted(Map reply) {
-    VMTester tester = new VMTester(reply);
-    tester.checkIsolateCount(2);
-  }
-}
-
-main() {
-  var process = new TestLauncher('multiple_isolate_list_script.dart');
-  process.launch().then((port) {
-    var test = new MultipleIsolateListTest(port);
-    test.makeRequest().then((_) {
-      process.requestExit();
-    });
-  });
-}