YARN-4328. Fix findbugs warnings in resourcemanager (Akira Ajisaka via Varun Saxena)

hadoop-yarn-project/hadoop-yarn/dev-support/findbugs-exclude.xml

@@ -394,4 +394,9 @@
     <Bug pattern="UI_INHERITANCE_UNSAFE_GETRESOURCE"/>
   </Match>
 
+  <Match>
+    <Class name="org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerApplicationAttempt" />
+    <Field name="queue" />
+    <Bug pattern="IS2_INCONSISTENT_SYNC" />
+  </Match>
 </FindBugsFilter>

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java

@@ -113,7 +113,7 @@ public class ZKRMStateStore extends RMStateStore {
   private List<ACL> zkAcl;
   private List<ZKUtil.ZKAuthInfo> zkAuths;
 
-  class ZKSyncOperationCallback implements AsyncCallback.VoidCallback {
+  static class ZKSyncOperationCallback implements AsyncCallback.VoidCallback {
     @Override
     public void processResult(int rc, String path, Object ctx){
       if (rc == Code.OK.intValue()) {