pgsql: Fix predicate-proving logic to cope with binary-compatibility - Mailing list pgsql-committers

Log Message:
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Fix predicate-proving logic to cope with binary-compatibility cases when
checking whether an IS NULL/IS NOT NULL clause is implied or refuted by
a strict function.  Per example from Dawid Kuroczko.
Backpatch to 8.2 since this is arguably a performance bug.

Modified Files:
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    pgsql/src/backend/optimizer/util:
        predtest.c (r1.15 -> r1.16)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/predtest.c.diff?r1=1.15&r2=1.16)