uses alias in HAVING when sql_mode = 'ONLY_FULL_GROUP_BY'

This patch corrects the patch for bug#18739: non-standard
HAVING extension was allowed in strict ANSI sql mode
added in 2006 by commit 4b7c4cd2.
As a result of incompleteness of the fix in the above commit
if a query with GROUP BY contained an aggregate function with an
alias and this alias was used in the HAVING clause of the query
the server reported an error when sql_mode was set to
'ONLY_FULL_GROUP_BY'.