YARN-3182. Cleanup switch statement in ApplicationMasterLauncher#handle(). Contributed by Ray Chiang.

(cherry picked from commit 110cf6b9a3b64cc2159e708967b854f5a419d438)

hadoop-yarn-project/CHANGES.txt

@@ -256,6 +256,9 @@ Release 2.7.0 - UNRELEASED
     YARN-3179. Update use of Iterator to Iterable in RMAdminCLI and
     CommonNodeLabelsManager. (Ray Chiang via xgong)
 
+    YARN-3182. Cleanup switch statement in ApplicationMasterLauncher#handle().
+    (Ray Chiang via ozawa)
+
   OPTIMIZATIONS
 
     YARN-2990. FairScheduler's delay-scheduling always waits for node-local and 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/amlauncher/ApplicationMasterLauncher.java

@@ -117,6 +117,7 @@ public class ApplicationMasterLauncher extends AbstractService implements
       break;
     case CLEANUP:
       cleanup(application);
+      break;
     default:
       break;
     }