Do not include univ.i in mysql_addons.h, it was included for the sole
purpose of innodb_redefine.h to work and now innodb_redefine.h has been
removed. See r2251 and r2288.
Include univ.i in mysql_addons.h because univ.i includes innodb_redefine.h
which is needed to rename the functions in this file with ibd_ prefix in
the dynamic InnoDB plugin. Aka the renaming magic, required for the dynamic
plugin to work.
Approved by: Marko
Introduce a generic soultion to the common problem that MySQL do not add
functions needed by us in a reasonable time.
Start with a function that retrieves THD::thread_id, this is needed for
the information_schema.innodb_trx.mysql_thread_id column.
Approved by: Marko
