Add step OverAwait to service protocol

runtime/observatory/tests/service/test_helper.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 test_helper;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 import 'package:observatory/service_io.dart';
@@ skipping 357 matching lines @@
   await isolate.resume();
   return completer.future;
 }
 
 IsolateTest resumeIsolateAndAwaitEvent(stream, onEvent) {
   return (Isolate isolate) async =>
       resumeAndAwaitEvent(isolate, stream, onEvent);
 }
 
 
+Future<Isolate> stepOver(Isolate isolate) async {
+  await isolate.stepOver();
+  return hasStoppedAtBreakpoint(isolate);
+}
+
 Future<Class> getClassFromRootLib(Isolate isolate, String className) async {
   Library rootLib = await isolate.rootLibrary.load();
   for (var i = 0; i < rootLib.classes.length; i++) {
     Class cls = rootLib.classes[i];
     if (cls.name == className) {
       return cls;
     }
   }
   return null;
 }
@@ skipping 63 matching lines @@
       }, onError: (e, st) {
         process.requestExit();
         if (!_isWebSocketDisconnect(e)) {
           print('Unexpected exception in service tests: $e $st');
           throw e;
         }
       });
     });
   }
 }