pgsql: pg_dump: fix mis-dumping of non-global default privileges.

pg_dump: fix mis-dumping of non-global default privileges.

Non-global default privilege entries should be dumped as-is,
not made relative to the default ACL for their object type.
This would typically only matter if one had revoked some
on-by-default privileges in a global entry, and then wanted
to grant them again in a non-global entry.

Per report from Boris Korzun.  This is an old bug, so back-patch
to all supported branches.

Neil Chen, test case by Masahiko Sawada

Discussion: https://postgr.es/m/111621616618184@mail.yandex.ru
Discussion: https://postgr.es/m/CAA3qoJnr2+1dVJObNtfec=qW4Z0nz=A9+r5bZKoTSy5RDjskMw@mail.gmail.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/10f9faf6d87393e3599e6892576d902d4ea07143

Modified Files
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src/bin/pg_dump/pg_dump.c        | 19 ++++++++++++++++++-
src/bin/pg_dump/t/002_pg_dump.pl | 40 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 58 insertions(+), 1 deletion(-)