Fix upgrade/downgrade issue.

mysql-test/r/ps_1general.result

@@ -325,6 +325,7 @@ NDB	YES/NO	Alias for NDBCLUSTER
 EXAMPLE	YES/NO	Example storage engine
 ARCHIVE	YES/NO	Archive storage engine
 CSV	YES/NO	CSV storage engine
+BLACKHOLE	YES/NO	Storage engine designed to act as null storage
 drop table if exists t5;
 prepare stmt1 from ' drop table if exists t5 ' ;
 execute stmt1 ;

sql/handler.h

@@ -150,8 +150,8 @@ enum db_type
   DB_TYPE_BERKELEY_DB, DB_TYPE_INNODB, 
   DB_TYPE_GEMINI, DB_TYPE_NDBCLUSTER,
   DB_TYPE_EXAMPLE_DB, DB_TYPE_ARCHIVE_DB, DB_TYPE_CSV_DB,
+  DB_TYPE_FEDERATED_DB,
   DB_TYPE_BLACKHOLE_DB,
-	       
   DB_TYPE_DEFAULT // Must be last
 };