bug #7215: information_schema: columns are longtext instead of varchar

into gluh.mysql.r18.ru:/home/gluh/MySQL/mysql-5.0

into serg.mylan:/usr/home/serg/Abk/mysql-5.0

into mysql.com:/home/jimw/my/mysql-4.1-clean

into mysql.com:/home/jimw/my/mysql-4.1-clean

into mysql.com:/home/psergey/mysql-5.0-bug8397

In Item_cache_decimal::store(item) the call item->val_decimal_result() 
returns NULL if the passed item has an SQL null value. Don't try copying
NULL into Item_cache_decimal::val in this case.

into mysql.com:/home/my/mysql-5.0

into serg.mylan:/usr/home/serg/Abk/mysql-5.0

into mysql.com:/home/psergey/mysql-5.0-build

into serg.mylan:/usr/home/serg/Abk/mysql-5.0

  Take into account that bitmap_is_set() may return any non-zero zero value when the bit is set.

into hundin.mysql.fi:/home/heikki/mysql-5.0

into mysql.com:/home/my/mysql-5.0

  Disable the XA code in InnoDB crash recovery; when Jan and Sergei want to test XA, they should revert this patch

into gluh.mysql.r18.ru:/home/gluh/MySQL/mysql-5.0

into mysql.com:/home/bkroot/mysql-4.1

into mysql.com:/home/my/mysql-4.1