Add more text output to service test pause_on_start_then_step_test

runtime/observatory/tests/service/pause_on_start_then_step_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 'package:observatory/models.dart' as M;
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 import 'dart:async';
@@ skipping 51 matching lines @@
     });
 
     print('Stepping...');
     isolate.stepInto();
 
     // Wait for the isolate to hit PauseBreakpoint.
     print('Waiting for PauseBreakpoint');
     await completer.future;
 
     // Grab the timestamp.
+    print('Getting pausevent timestamp');
     var pausetime2 = isolate.pauseEvent.timestamp;
     expect(pausetime2, isNotNull);
     // Reload the isolate.
+    print('Reloading isolate');
     await isolate.reload();
+    print('Reload finished');
     // Verify that it is the same.
     expect(pausetime2.millisecondsSinceEpoch,
         equals(isolate.pauseEvent.timestamp.millisecondsSinceEpoch));
 
     expect(pausetime2.millisecondsSinceEpoch,
         greaterThan(pausetime1.millisecondsSinceEpoch));
+
+    print('Test finished');
   },
 ];
 
 main(args) => runIsolateTests(args, tests,
     testeeConcurrent: testMain,
     pause_on_start: true,
     pause_on_exit: true,
     verbose_vm: true,
     extraArgs: ['--trace-service', '--trace-service-verbose']);