pgsql: Clear CurrentResourceOwner earlier in CommitTransaction.

Clear CurrentResourceOwner earlier in CommitTransaction.

Alexander reported a crash with repeated create + drop database, after
the ResourceOwner rewrite (commit b8bff07daa). That was fixed by the
previous commit, but it nevertheless seems like a good idea clear
CurrentResourceOwner earlier, because you're not supposed to use it
for anything after we start releasing it.

Reviewed-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/11b70743-c5f3-3910-8e5b-dd6c115ff829%40gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c21e6e2fd48cdcfe7d01eed243d576c722ef8de5

Modified Files
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src/backend/access/transam/xact.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)