RE: Logical replication 'invalid memory alloc request size 1585837200' after upgrading to 17.5

Dear hackers,

> Attached are the patches, including those required for the back branches.

While reviewing patch for PG13, I found the doubtful point in ReorderBufferCommit().

```
            /*
             * Every time the CommandId is incremented, we could
             * see new catalog contents, so execute all
             * invalidations.
             */
            ReorderBufferExecuteInvalidations(txn->ninvalidations,
                             txn->invalidations);
```

This is called when REORDER_BUFFER_CHANGE_INTERNAL_COMMAND_ID is dequeued from the
change queue, and this part exists only in PG13 codebase.
We are not sure whether we should execute txn->invalidations_distributed as well.
This can affect below case:

txn1: BEGIN; INSERT INTO d VALUES ('d1');
txn2: ALTER PUBLICATION pb ADD TABLE d;
txn1: CREATE TABLE another (id int);
txn1: INSERT INTO d VALUES ('d2');
txn1: COMMIT;
-> PG13 - no output
-> PG13 + v13 patch - no output
-> PG13 + v13 patch + additional inval execution - d2 can be replicated
-> (master - d2 can be replicated)

Personally I think txn->invalidations_distributed is not needed to be executed
because the spec seems bit complex, but I want to know other opinion.

Best regards,
Hayato Kuroda
FUJITSU LIMITED