pgsql: Repair incorrect placement of WHERE clauses when there are

Log Message:
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Repair incorrect placement of WHERE clauses when there are multiple,
rearrangeable outer joins and the WHERE clause is non-strict and mentions
only nullable-side relations.  New bug in 8.2, caused by new logic to allow
rearranging outer joins.  Per bug #2807 from Ross Cohen; thanks to Jeff
Davis for producing a usable test case.

Modified Files:
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    pgsql/src/backend/optimizer/plan:
        initsplan.c (r1.123 -> r1.124)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/plan/initsplan.c.diff?r1=1.123&r2=1.124)