pgsql: Fix bogus handling of "postponed" lateral quals.

Fix bogus handling of "postponed" lateral quals.

When pulling a "postponed" qual from a LATERAL subquery up into the quals
of an outer join, we must make sure that the postponed qual is included
in those seen by make_outerjoininfo(). Otherwise we might compute a
too-small min_lefthand or min_righthand for the outer join, leading to
"JOIN qualification cannot refer to other relations" failures from
distribute_qual_to_rels. Subtler errors in the created plan seem possible,
too, if the extra qual would only affect join ordering constraints.

Per bug #9041 from David Leverton. Back-patch to 9.3.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/043f6ff05d0a5140dfe25faf277ec9f1d7169005

Modified Files
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src/backend/optimizer/plan/initsplan.c | 56 +++++++++++++++++---------------
src/test/regress/expected/join.out | 22 +++++++++++++
src/test/regress/sql/join.sql | 8 +++++
3 files changed, 59 insertions(+), 27 deletions(-)