Not quite sure that we don't need to do anything for the WINDOWAGG_PASSTHROUGH_STRICT case. Although, we won't return any more tuples for the current partition, we still call ExecProject with dangling pointers. Is it okay?
AFAIU once we go into WINDOWAGG_PASSTHROUGH_STRICT we will spool all the remaining tuples in the current partition without storing them and then move to the next partition if available and become WINDOWAGG_RUN again or become WINDOWAGG_DONE if there are no further partitions. It seems we would not have chance to see the dangling pointers.
+ if (!func_strict(opexpr->opfuncid)) + return false;
