pgsql: Fix make_greater_string to not have an undocumented collation as

Fix make_greater_string to not have an undocumented collation assumption.

The previous coding worked only if ltproc->fn_collation was always either
DEFAULT_COLLATION_OID or a C-compatible locale.  While that's true at the
moment, it wasn't documented (and in fact wasn't true when this code was
committed...).  But it only takes a couple more lines to make its internal
caching behavior locale-aware, so let's do that.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/466dac8656c11317b91c1a4bfd5cfca4508cba94

Modified Files
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src/backend/utils/adt/selfuncs.c |   13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)