Remove --compile_all from all but one service test

runtime/observatory/tests/service/async_scope_test.dart

 // Copyright (c) 2015, 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
+// VMOptions=--error_on_bad_type --error_on_bad_override
 
 import 'dart:developer';
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 
 foo() {}
 
 doAsync(param1) async {
   var local1 = param1 + 1;
@@ skipping 47 matching lines @@
   checkAsyncVarDescriptors,
   resumeIsolate,
 
   hasStoppedAtBreakpoint,
   stoppedAtLine(21),
   checkAsyncStarVarDescriptors,
   resumeIsolate,
 ];
 
 main(args) => runIsolateTests(args, tests, testeeConcurrent: testeeDo);