Enable strict flags for all service tests

runtime/observatory/test/malformed_test.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.
+// VMOptions=--compile-all --error_on_bad_type --error_on_bad_override --checked
 
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 
 var tests = [
 
 (Isolate isolate) =>
   isolate.invokeRpc('_respondWithMalformedJson', { }).then((result) {
     // Should not execute.
     expect(true, false);
   }).catchError((ServiceException exception) {
     expect(exception.kind, equals('JSONDecodeException'));
   }),
 
 (Isolate isolate) =>
   isolate.invokeRpc('_respondWithMalformedObject', { }).then((result) {
     // Should not execute.
     expect(true, false);
   }).catchError((ServiceException exception) {
     expect(exception.kind, equals('ResponseFormatException'));
   }),
 ];
 
 main(args) => runIsolateTests(args, tests);