Bug #20770 Partitions not removed after reorganize.

Description:
The files 

tb5_eng1#P#part9#SP#subpart92.MYD
tb5_eng1#P#part9#SP#subpart92.MYI

still exist after the following ALTER...REORGANIZE statements:

ALTER TABLE tb5_eng1 REORGANIZE PARTITION part2 INTO
 (PARTITION part8 values in (5,6) $data_directory $index_directory (SUBPARTITION subpart81, SUBPARTITION subpart82),
  PARTITION part9 values in (7,8) $data_directory $index_directory (SUBPARTITION subpart91, SUBPARTITION subpart92));

ALTER TABLE tb5_eng1 REORGANIZE PARTITION part8,part9 INTO
 (PARTITION part2 values in (5,6,7,8) $data_directory $index_directory 
(SUBPARTITION subpart21, SUBPARTITION subpart22));

See program attached.

How to repeat:
perl mysql-test-run.pl error_reorg_part2_8_92

program to reproduce the bug

Attachment: error_reorg_part2_8_92.test (application/octet-stream, text), 1.81 KiB.

Thank you for the bug report. Verified as described:
miguel@hegel:~/dbs/mysql-5.1/mysql-test/var/master-data/test> ls tb5_eng1#P#part9#SP#subpart92*
tb5_eng1#P#part9#SP#subpart92.MYD  tb5_eng1#P#part9#SP#subpart92.MYI

Needed to call set_up_table_before_create also when altering partitions
Also found an error in default handling of options for subpartitions while at it

Will appear in 5.1.12

Documented bugfix in 5.1.12 changelog.