pgsql: Don't include outer join relids in lateral_relids bitmapsets.

Don't include outer join relids in lateral_relids bitmapsets.

This avoids an assertion failure when outer joins are rearranged
per identity 3. Listing only the baserels from a PlaceHolderVar's
ph_lateral set should be enough to ensure that the required values
are available when we need to compute the PHV --- it's what we
did before inventing nullingrel sets, after all. It's a bit
unsatisfying; but with beta2 hard upon us, there's not time to
look for an aesthetically cleaner fix.

Richard Guo and Tom Lane

Discussion: https://postgr.es/m/CAMbWs48Jcw-NvnxT23WiHP324wG44DvzcH1j4hc0Zn+3sR9cfg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/efeb12ef0bfef0b5aa966a56bb4dbb1f936bda0c

Modified Files
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src/backend/optimizer/plan/initsplan.c | 16 +++++++++++++---
src/test/regress/expected/join.out | 17 +++++++++++++++++
src/test/regress/sql/join.sql | 7 +++++++
3 files changed, 37 insertions(+), 3 deletions(-)