pgsql: expression eval: Don't redundantly keep track of AggState.

expression eval: Don't redundantly keep track of AggState.

It's already tracked via ExprState->parent, so we don't need to also
include it in ExprEvalStep. When that code originally was written
ExprState->parent didn't exist, but it since has been introduced in
6719b238e8f.

Author: Andres Freund
Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1fdb7f9789c4550204cd62d1746a7deed1dc4c29

Modified Files
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src/backend/executor/execExpr.c | 5 -----
src/backend/executor/execExprInterp.c | 17 +++++++----------
src/backend/jit/llvm/llvmjit_expr.c | 23 ++++++++++++-----------
src/include/executor/execExpr.h | 5 -----
src/include/nodes/execnodes.h | 1 +
5 files changed, 20 insertions(+), 31 deletions(-)