fix doc.

Author: hfutatzhanghb

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/async/RouterAsyncClientProtocol.java

@@ -1055,7 +1055,6 @@ public boolean setReplication(String src, short replication)
    * @param src the source path
    * @return true if the path is directory and is supposed to be present in all
    *         subclusters else false in all other scenarios.
-   * @throws IOException if unable to get the file status.
    */
   @VisibleForTesting
   @Override

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/router/async/TestRouterAsyncRPCMultipleDestinationMountTableResolver.java

@@ -46,6 +46,9 @@
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
+/**
+ * Tests router async rpc with multiple destination mount table resolver.
+ */
 public class TestRouterAsyncRPCMultipleDestinationMountTableResolver extends
     TestRouterRPCMultipleDestinationMountTableResolver {