pgsql: Reset per-tuple memory context between every row in a scan node,

Reset per-tuple memory context between every row in a scan node, even when
there's no quals or projections. Currently this only matters for foreign
scans, as none of the other scan nodes litter the per-tuple memory context
when there's no quals or projections.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0319da638f337cae66a4649581dc1f33d5079e1a

Modified Files
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src/backend/executor/execScan.c |    5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)