pgsql: Simplify vacuum visibility assertion

Simplify vacuum visibility assertion

Phase I vacuum gives the page a once-over after pruning and freezing to
check that the values of all_visible and all_frozen agree with the
result of heap_page_is_all_visible(). This is meant to keep the logic in
phase I for determining visibility in sync with the logic in phase III.

Rewrite the assertion to avoid an Assert(false).

Suggested by Andres Freund.

Author: Melanie Plageman <melanieplageman(at)gmail(dot)com>
Discussion: https://postgr.es/m/mhf4vkmh3j57zx7vuxp4jagtdzwhu3573pgfpmnjwqa6i6yj5y%40sy4ymcdtdklo

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bd298f54a0d60a0376959e10074aa07cbad267f2

Modified Files
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src/backend/access/heap/vacuumlazy.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)