pgsql-server: Repair 'expected both swapped tables to have TOAST tables'

Log Message:
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Repair 'expected both swapped tables to have TOAST tables' bug in 7.4
branch.  I wasn't excited about doing this when the first report came in,
but now that we have two of 'em, I suppose it had better get fixed.

Tags:
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REL7_4_STABLE

Modified Files:
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    pgsql-server/src/backend/commands:
        cluster.c (r1.116 -> r1.116.2.1)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/commands/cluster.c.diff?r1=1.116&r2=1.116.2.1)