HADOOP-10668. Addendum patch to fix TestZKFailoverController. Contributed by Ming Ma.

(cherry picked from commit 925c9fed3311ea1fd8f5ed1cb6b1c0abc5c90425)

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ha/MiniZKFCCluster.java

@@ -155,6 +155,11 @@ public class MiniZKFCCluster {
 
   /**
    * Wait for the given HA service to enter the given HA state.
+   * This is based on the state of ZKFC, not the state of HA service.
+   * There could be difference between the two. For example,
+   * When the service becomes unhealthy, ZKFC will quit ZK election and
+   * transition to HAServiceState.INITIALIZING and remain in that state
+   * until the service becomes healthy.
    */
   public void waitForHAState(int idx, HAServiceState state)
       throws Exception {

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ha/TestZKFailoverController.java

@@ -211,8 +211,8 @@ public class TestZKFailoverController extends ClientBaseWithFixes {
       LOG.info("Faking svc0 unhealthy, should failover to svc1");
       cluster.setHealthy(0, false);
       
-      LOG.info("Waiting for svc0 to enter standby state");
-      cluster.waitForHAState(0, HAServiceState.STANDBY);
+      LOG.info("Waiting for svc0 to enter initializing state");
+      cluster.waitForHAState(0, HAServiceState.INITIALIZING);
       cluster.waitForHAState(1, HAServiceState.ACTIVE);
   
       LOG.info("Allowing svc0 to be healthy again, making svc1 unreachable " +
@@ -332,7 +332,7 @@ public class TestZKFailoverController extends ClientBaseWithFixes {
       Mockito.verify(svc1.proxy, Mockito.timeout(2000).atLeastOnce())
         .transitionToActive(Mockito.<StateChangeRequestInfo>any());
 
-      cluster.waitForHAState(0, HAServiceState.STANDBY);
+      cluster.waitForHAState(0, HAServiceState.INITIALIZING);
       cluster.waitForHAState(1, HAServiceState.STANDBY);
       
       LOG.info("Faking svc0 healthy again, should go back to svc0");
@@ -587,12 +587,12 @@ public class TestZKFailoverController extends ClientBaseWithFixes {
 
       // Failover by bad health
       cluster.setHealthy(0, false);
-      cluster.waitForHAState(0, HAServiceState.STANDBY);
+      cluster.waitForHAState(0, HAServiceState.INITIALIZING);
       cluster.waitForHAState(1, HAServiceState.ACTIVE);
       cluster.setHealthy(1, true);
       cluster.setHealthy(0, false);
       cluster.waitForHAState(1, HAServiceState.ACTIVE);
-      cluster.waitForHAState(0, HAServiceState.STANDBY);
+      cluster.waitForHAState(0, HAServiceState.INITIALIZING);
       cluster.setHealthy(0, true);
       
       cluster.waitForHealthState(0, State.SERVICE_HEALTHY);