Bug#27333: subquery grouped for aggregate of outer
query / no aggregate of subquery The optimizer counts the aggregate functions that appear as top level expressions (in all_fields) in the current subquery. Later it makes a list of these that it uses to actually execute the aggregates in end_send_group(). That count is used in several places as a flag whether there are aggregates functions. While collecting the above info it must not consider aggregates that are not aggregated in the current context. It must treat them as normal expressions instead. Not doing that leads to incorrect data about the query, e.g. running a query that actually has no aggregate functions as if it has some (and hence is expected to return only one row). Fixed by ignoring the aggregates that are not aggregated in the current context. One other smaller omission discovered and fixed in the process : the place of aggregation was not calculated for user defined functions. Fixed by calling Item_sum::init_sum_func_check() and Item_sum::check_sum_func() as it's done for the rest of the aggregate functions.
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