pgsql: amcheck: Improve some confusing reports about TOAST problems.

amcheck: Improve some confusing reports about TOAST problems.

Don't phrase reports in terms of the number of tuples thus-far
returned by the index scan, but rather in terms of the chunk_seq
values found inside the tuples.

Patch by me, reviewed by Mark Dilger.

Discussion: http://postgr.es/m/CA+TgmoZUONCkdcdR778EKuE+f1r5Obieu63db2OgMPHaEvEPTQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/50529e5b4e39ad80a637ba0905277f9691eb4a15

Modified Files
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contrib/amcheck/verify_heapam.c | 75 ++++++++++++++++++++++-------------------
1 file changed, 40 insertions(+), 35 deletions(-)