HDFS-10868. Remove stray references to DFS_HDFS_BLOCKS_METADATA_ENABLED.

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

@@ -131,9 +131,6 @@ public interface HdfsClientConfigKeys {
           "dfs.client.key.provider.cache.expiry";
   long    DFS_CLIENT_KEY_PROVIDER_CACHE_EXPIRY_DEFAULT =
               TimeUnit.DAYS.toMillis(10); // 10 days
-  String  DFS_HDFS_BLOCKS_METADATA_ENABLED =
-      "dfs.datanode.hdfs-blocks-metadata.enabled";
-  boolean DFS_HDFS_BLOCKS_METADATA_ENABLED_DEFAULT = false;
 
   String  DFS_DATANODE_KERBEROS_PRINCIPAL_KEY =
       "dfs.datanode.kerberos.principal";

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -58,10 +58,6 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
       .DFS_CHECKSUM_TYPE_KEY;
   public static final String  DFS_CHECKSUM_TYPE_DEFAULT =
       HdfsClientConfigKeys.DFS_CHECKSUM_TYPE_DEFAULT;
-  public static final String  DFS_HDFS_BLOCKS_METADATA_ENABLED =
-      HdfsClientConfigKeys.DFS_HDFS_BLOCKS_METADATA_ENABLED;
-  public static final boolean DFS_HDFS_BLOCKS_METADATA_ENABLED_DEFAULT =
-      HdfsClientConfigKeys.DFS_HDFS_BLOCKS_METADATA_ENABLED_DEFAULT;
   public static final String DFS_WEBHDFS_ACL_PERMISSION_PATTERN_DEFAULT =
       HdfsClientConfigKeys.DFS_WEBHDFS_ACL_PERMISSION_PATTERN_DEFAULT;
   public static final String  DFS_WEBHDFS_NETTY_LOW_WATERMARK =

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestHdfsConfigFields.java

@@ -75,8 +75,6 @@ public class TestHdfsConfigFields extends TestConfigurationFieldsBase {
     // Fully deprecated properties?
     configurationPropsToSkipCompare
         .add("dfs.corruptfilesreturned.max");
-    configurationPropsToSkipCompare
-        .add("dfs.datanode.hdfs-blocks-metadata.enabled");
     configurationPropsToSkipCompare
         .add("dfs.metrics.session-id");
     configurationPropsToSkipCompare