Remove flaky check from reanalyze_concurrent_test.

pkg/analysis_server/test/integration/analysis/reanalyze_concurrent_test.dart

 // Copyright (c) 2014, 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.
 
 /**
  * This test verifies that if reanalysis is performed while reanalysis is in
  * progress, no problems occur.
  *
  * See dartbug.com/21448.
  */
 library test.integration.analysis.reanalyze_concurrent;
 
 import 'dart:async';
 
-import 'package:analysis_server/src/protocol.dart';
-import 'package:unittest/unittest.dart';
-
 import '../../reflective_tests.dart';
 import '../integration_tests.dart';
 
 main() {
   runReflectiveTests(Test);
 }
 
 @ReflectiveTestCase()
 class Test extends AbstractAnalysisServerIntegrationTest {
   test_reanalyze_concurrent() {
     String pathname = sourcePath('test.dart');
     String text = '''
 // Do a bunch of imports so that analysis has some work to do.
 import 'dart:io';
 import 'dart:convert';
 import 'dart:async';
 
 main() {}''';
     writeFile(pathname, text);
     standardAnalysisSetup();
     return analysisFinished.then((_) {
       sendAnalysisReanalyze();
       // Wait for reanalysis to start.
       return onServerStatus.first.then((_) {
         sendAnalysisReanalyze();
         return analysisFinished.then((_) {
-          // Now that reanalysis has finished, no further analysis should occur.
-          onServerStatus.listen((ServerStatusParams data) {
-            if (data.analysis != null) {
-              if (data.analysis.isAnalyzing) {
-                // Most likely what happened is that the first reanalyze
-                // completed before the second reanalyze had a chance to start,
-                // and we are just now starting the second reanalyze.  If this
-                // is the case, then the test isn't testing what it's meant to
-                // test (because we are trying to test what happens when one
-                // reanalyze starts while another is in progress).  In which
-                // case we will need to give the analyzer more work to do.
-                fail('First reanalyze finished before second started.');
-              }
-            }
-          });
-          // Give the server an extra second to make sure it doesn't take any
-          // more actions.
+          // Now that reanalysis has finished, give the server an extra second
+          // to make sure it doesn't crash.
           return new Future.delayed(new Duration(seconds: 1));
         });
       });
     });
   }
 }