Re: Subscription test 013_partition.pl fails under CLOBBER_CACHE_ALWAYS

I wrote:
> It's not really clear to me why setting localreloid to zero is a sane
> way to represent "this entry needs to be revalidated". I think a
> separate flag would be more appropriate. Once we have lock on the
> target relation, it seems to me that no interesting changes should
> be possible as long as we have lock; so there's no very good reason
> to destroy useful state to remind ourselves that we should recheck
> it next time.

Here's a patch that changes that, and also cleans up some sloppy
thinking about how to re-acquire lock on the replication target
relation. (Just because the OID was valid last you heard does
not mean that table_open is guaranteed to succeed.)

With this, we get through 013_partition.pl under CCA. I plan to
try to run all of subscription/ and recovery/ before concluding
there's nothing else to fix, though.

regards, tom lane