pgsql: Acquire locks on views in AcquirePlannerLocks, too.

Acquire locks on views in AcquirePlannerLocks, too.

Commit 47bb9db75 taught AcquireExecutorLocks to re-acquire locks
on views using data from their RTE_SUBQUERY replacements, but
it now seems like we should make AcquirePlannerLocks do the same.
In this way, if a view has been redefined, we will notice that
a bit earlier while checking validity of a cached plan and thereby
avoid some wasted work.

Report and patch by Amit Langote.

Discussion: https://postgr.es/m/CA+HiwqH0xZOQ+GQAdKeckY1R4NOeHdzhtfxkAMJLSchpapNk5w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/65eb2d00c6c1bab29db9fa6575185a40d823fe9d

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