sql/sp.cc:
  Bugfixes for the sp_head memroot stuff. (Do things in the correct order
  at error clean-up.)
sql/sp_head.cc:
  Bugfixes for the sp_head memroot stuff. Make sure everything goes to the
  right memroot. Need separate post-reset-memroot init in sp_head.
sql/sp_head.h:
  Need separate post-reset-memroot init method.
sql/sql_yacc.yy:
  Bugfixes for the sp_head memroot stuff. Make sure everything goes to the
  right memroot. Must do things in the correct order for this.