Add hasStoppedAtBreakpoint

runtime/observatory/tests/service/get_stack_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=--compile-all --error_on_bad_type --error_on_bad_override
 
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 import 'dart:async';
 import 'dart:isolate' as isolate;
@@ skipping 19 matching lines @@
   new Timer.periodic(const Duration(milliseconds:10), periodicTask);
 }
 
 var tests = [
 
 // Initial data fetch and verify we've hit the breakpoint.
 (Isolate isolate) async {
   await isolate.rootLib.load();
   var script = isolate.rootLib.scripts[0];
   await script.load();
+  await hasStoppedAtBreakpoint(isolate);
+  // Sanity check.
   expect(isolate.pauseEvent.eventType, equals(ServiceEvent.kPauseBreakpoint));
 },
 
 // Get stack
 (Isolate isolate) async {
   var stack = await isolate.getStack();
   expect(stack.type, equals('Stack'));
 
   // Sanity check.
   expect(stack['frames'].length, greaterThanOrEqualTo(1));
@@ skipping 36 matching lines @@
   expect(msgHandlerObjectId, isNotNull);
 
   // Get object.
   var object = await isolate.getObject(msgHandlerObjectId);
   expect(object.valueAsString, equals('34'));
 }
 
 ];
 
 main(args) => runIsolateTests(args, tests, testeeBefore: startTimer);