HDFS-8620. Clean up the checkstyle warinings about ClientProtocol. Contributed by Takanobu Asanuma.

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/HdfsClientConfigKeys.java

@@ -39,7 +39,8 @@ public interface HdfsClientConfigKeys {
   String  DFS_NAMENODE_HTTPS_ADDRESS_KEY = "dfs.namenode.https-address";
   String DFS_HA_NAMENODES_KEY_PREFIX = "dfs.ha.namenodes";
   int DFS_NAMENODE_RPC_PORT_DEFAULT = 8020;
-  String DFS_NAMENODE_KERBEROS_PRINCIPAL_KEY = "dfs.namenode.kerberos.principal";
+  String DFS_NAMENODE_KERBEROS_PRINCIPAL_KEY =
+      "dfs.namenode.kerberos.principal";
 
   /** dfs.client.retry configuration properties */
   interface Retry {

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -704,6 +704,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-8711. setSpaceQuota command should print the available storage type
     when input storage type is wrong. (Brahma Reddy Battula via xyao)
 
+    HDFS-8620. Clean up the checkstyle warinings about ClientProtocol.
+    (Takanobu Asanuma via wheat9)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than