pgsql: Fix handling of extension membership when filling in a shell ope

Fix handling of extension membership when filling in a shell operator.

The previous coding would result in deleting and not re-creating the
extension membership pg_depend rows, since there was no
CommandCounterIncrement that would allow recordDependencyOnCurrentExtension
to see that the deletion had happened.  Make it work like the shell type
case, ie, keep the existing entries (and then throw an error if they're for
the wrong extension).

Per bug #6172 from Hitoshi Harada.  Investigation and fix by Dimitri
Fontaine.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/9c471d24126280a5f90ee9d276a9df37480dfcde

Modified Files
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src/backend/catalog/pg_operator.c |    7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)