MAPREDUCE-6675. TestJobImpl.testUnusableNode failed (haibochen via rkanter)

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/test/java/org/apache/hadoop/mapreduce/v2/app/job/impl/TestJobImpl.java

@@ -531,7 +531,7 @@ public class TestJobImpl {
     Configuration conf = new Configuration();
     conf.set(MRJobConfig.MR_AM_STAGING_DIR, stagingDir);
     conf.setInt(MRJobConfig.NUM_REDUCES, 1);
-    AsyncDispatcher dispatcher = new AsyncDispatcher();
+    DrainDispatcher dispatcher = new DrainDispatcher();
     dispatcher.init(conf);
     dispatcher.start();
     CyclicBarrier syncBarrier = new CyclicBarrier(2);
@@ -608,6 +608,7 @@ public class TestJobImpl {
     NodeReport secondMapperNodeReport = nodeReports.get(1);
     job.handle(new JobUpdatedNodesEvent(job.getID(),
         Collections.singletonList(firstMapperNodeReport)));
+    dispatcher.await();
     // complete the reducer
     for (TaskId taskId: job.tasks.keySet()) {
       if (taskId.getTaskType() == TaskType.REDUCE) {