Re: BUG #18953: Planner fails to build plan for complex query with LATERAL references

So I'm inclined to leave that code as I had it.  It's notationally
a bit simpler and it doesn't require assuming that we can ignore
the path's required_outer marking at this stage.  If I'm wrong,
someone will eventually find a counterexample and we can fix it
then; the changes won't be large.

Please look at the following (simplified version of a query generated by
SQLsmith), which produces errors after a16ef313f2:
CREATE TABLE t(b bool); ANALYZE t;

SELECT 1 FROM t
INNER JOIN (SELECT (SELECT true) AS c FROM t, LATERAL (SELECT b LIMIT 1)) ON true
RIGHT JOIN (SELECT true) ON true,
LATERAL (SELECT b WHERE c LIMIT 1)
WHERE t.b;
ERROR:  XX000: unrecognized node type: 22
LOCATION:  ExecInitExprRec, execExpr.c:2665

Or a slight variation:
SELECT 1 FROM t
INNER JOIN (SELECT (SELECT true) AS c FROM t, LATERAL (SELECT 1 LIMIT 1)) ON true
RIGHT JOIN (SELECT true) ON true,
LATERAL (SELECT b WHERE c LIMIT 1)
WHERE t.b;
ERROR:  XX000: failed to assign all NestLoopParams to plan nodes
LOCATION:  create_plan, createplan.c:372

Best regards,
Alexander