pgsql: Fire create_upper_paths_hook for UPPERREL_PARTIAL_GROUP_AGG

Fire create_upper_paths_hook for UPPERREL_PARTIAL_GROUP_AGG

create_partial_grouping_paths() called the FDW callback
GetForeignUpperPaths for UPPERREL_PARTIAL_GROUP_AGG, but never the
general-purpose create_upper_paths_hook that non-FDW extensions rely
on. create_partial_distinct_paths() already fires both for
UPPERREL_PARTIAL_DISTINCT.

Add the missing call right next to GetForeignUpperPaths, so an
extension can add partial-aggregate paths here too, before the caller
gathers them and builds a Finalize Aggregate on top.

Reviewed-by: Bryan Green <dbryan(dot)green(at)gmail(dot)com>
Reviewed-by: Himanshu Upadhyaya <upadhyaya(dot)himanshu(at)gmail(dot)com>
Reviewed-by: Shihao Zhong <zhong950419(at)gmail(dot)com>
Discussion: https://postgr.es/m/6fc72a7d-9f52-4a72-9adf-1912da255605@dunslane.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e8a82ddeaf69b077125cf9303df809234461bd37

Modified Files
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src/backend/optimizer/plan/planner.c | 6 ++++++
1 file changed, 6 insertions(+)