Bug #61768 ALTER TABLE alter_specifications are order sensitive

Description:
alter table add a column using AFTER another column, if the another column also in the alter table clause and using AFTER, error occurs.
if reverse the alter_specifications, it might work.

How to repeat:
mysql> create table dummy (foo int, bar int);
Query OK, 0 rows affected (0.01 sec)
mysql> alter table dummy add column baz int after foo, change column foo foo int after bar;
ERROR 1054 (42S22): Unknown column 'foo' in 'dummy'
mysql> alter table dummy change column foo foo int after bar, add column baz int after foo;
Query OK, 0 rows affected (0.03 sec)
Records: 0  Duplicates: 0  Warnings: 0

Verified with current mysql-5.0 and mysql-5.5 on Mac OS X also:

macbook-pro:5.5 openxs$ bin/mysql -uroot test
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.15-debug Source distribution

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owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> create table dummy (foo int, bar int);
Query OK, 0 rows affected (0.25 sec)

mysql>  alter table dummy add column baz int after foo, change column foo foo int after
    -> bar;
ERROR 1054 (42S22): Unknown column 'foo' in 'dummy'
mysql> alter table dummy change column foo foo int after bar, add column baz int after
    -> foo;
Query OK, 0 rows affected (0.24 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> show create table dummy\G
*************************** 1. row ***************************
       Table: dummy
Create Table: CREATE TABLE `dummy` (
  `bar` int(11) DEFAULT NULL,
  `foo` int(11) DEFAULT NULL,
  `baz` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)