Refactor service tests in preparation of running on sky_shell

runtime/observatory/tests/service/evaluate_in_frame_rpc_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=--error_on_bad_type --error_on_bad_override
 
-import 'dart:async';
 import 'dart:developer';
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
+import 'service_test_common.dart';
 import 'test_helper.dart';
 
 void method(int value, _) {
   debugger();
 }
 
 void testFunction() {
   int i = 0;
   while (true) {
     if (++i % 100000000 == 0) {
@@ skipping 18 matching lines @@
   result = await isolate.evalFrame(0, 'value + _');
   expect(result.valueAsString, equals('10050'));
 
   result = await isolate.evalFrame(1, 'i');
   expect(result.valueAsString, equals('100000000'));
 },
 
 ];
 
 main(args) => runIsolateTests(args, tests, testeeConcurrent: testFunction);