pgsql: Accept invalidation messages in InitializeSessionUserId().

Accept invalidation messages in InitializeSessionUserId().

If the authentication method modified the system catalogs through a
separate database connection (say, to create a new role on the fly),
make sure syscache sees the changes before we try to find the user.

Author: Thomas Munro
Reviewed-by: Tom Lane, Andres Freund
Discussion: https://postgr.es/m/CAEepm%3D3_h0_cgmz5PMyab4xk_OFrg6G5VCN%3DnF4chFXM9iFOqA%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e8d9caa436db2931613d7cb4a4a8b3933d5f6ded

Modified Files
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src/backend/utils/init/miscinit.c | 8 ++++++++
1 file changed, 8 insertions(+)