pgsql: Set procost to 10 for each of the pg_foo_is_visible() functions.

Set procost to 10 for each of the pg_foo_is_visible() functions.

The idea here is to make sure the planner will evaluate these functions
last not first among the filter conditions in psql pattern search and
tab-completion queries. We've discussed this several times, and there
was consensus to do it back in August, but we didn't want to do it just
before a release. Now seems like a safer time.

No catversion bump, since this catalog change doesn't create a backend
incompatibility nor any regression test result changes.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a80889a7359e720107b881bcd3e8fd47f3874e36

Modified Files
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src/include/catalog/pg_proc.h | 24 ++++++++++++------------
1 files changed, 12 insertions(+), 12 deletions(-)