Bug#17559867 AFTER REBUILDING,A MYISAM PARTITION ENDS UP

             AS A INNODB PARTITTION.

PROBLEM
-------
The correct engine_type was not being set during 
rebuild of the partition due to which the handler
was always created with the default engine,
which is innodb for 5.5+ ,therefore even if the
table was myisam, after rebuilding the partitions
ended up as innodb partitions.

FIX
---
Set the correct engine type during rebuild.  

[Approved by mattiasj #rb3599]

sql/sql_partition.cc

@@ -4725,6 +4725,8 @@ that are reorganised.
     {
       uint no_parts_found;
       uint no_parts_opt= alter_info->partition_names.elements;
+      set_engine_all_partitions(tab_part_info,
+                                tab_part_info->default_engine_type);
       no_parts_found= set_part_state(alter_info, tab_part_info, PART_CHANGED);
       if (no_parts_found != no_parts_opt &&
           (!(alter_info->flags & ALTER_ALL_PARTITION)))