Null-merge from mysql-5.5.7-rc-release.

Null-merging revision
'revid: joerg@mysql.com-20101102213229-lyd8tl5gr40dotck'
(Bug_57916: Fix the naming of the proxy_priv table)
from mysql-5.5.7-rc-release.

The patch is already in mysq-5.5.8-release
(revid: georgi.kodinov@oracle.com-20101102154526-coc3muh4mlw91ti8)