pgsql: Copy collencoding in CREATE COLLATION / FROM

Copy collencoding in CREATE COLLATION / FROM

This command used to compute the collencoding entry like when a
completely new collation is created. But for example when copying the
"C" collation, this would then result in a collation that has a
collencoding entry for the current database encoding rather than -1,
thus not making an exact copy. This has probably no practical impact,
but making this change keeps the catalog contents neat.

Reported-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/54baa48139ae6b67347bea6a9183d494e625939b

Modified Files
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src/backend/commands/collationcmds.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)