pgsql: Fix pg_dump's handling of extension-member casts and languages.

Fix pg_dump's handling of extension-member casts and languages.

pg_dump has some heuristic rules for whether to dump casts and procedural
languages, since it's not all that easy to distinguish built-in ones from
user-defined ones. However, we should not apply those rules to objects
that belong to an extension, but just use the perfectly well-defined rules
for what to do with extension member objects. Otherwise we might
mistakenly lose extension member objects during a binary upgrade (which is
the only time that we'd want to dump extension members).

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b3bc63efbc258874b06586aa7548fce37f3581e1

Modified Files
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src/bin/pg_dump/pg_dump.c | 87 +++++++++++++++++++++++++++------------------
1 files changed, 52 insertions(+), 35 deletions(-)