[4.2.x] Fixed #34987 -- Fixed queryset crash when mixing aggregate and window annotations.

Regression in f387d024fc75569d2a4a338bfda76cc2f328f627.

Just like `OrderByList` the `ExpressionList` expression used to wrap
`Window.partition_by` must implement `get_group_by_cols` to ensure the
necessary grouping when mixing window expressions with aggregate
annotations is performed against the partition members and not the
partition expression itself.

This is necessary because while `partition_by` is implemented as
a source expression of `Window` it's actually a fragment of the WINDOW
expression at the SQL level and thus it should result in a group by its
members and not the sum of them.

Thanks ElRoberto538 for the report.
Backport of e76cc93b0168fa3abbafb9af1ab4535814b751f0 from main

0 files changed, 0 insertions, 0 deletions