pg_get_viewdef returns one paren too much

laurie(dot)burrow(at)powerconv(dot)alstom(dot)com noticed a problem with pg_get_viewdef
in prettyprint mode.

create table gnrcitm (gnrcitmid int);
create table gnrcitmothrref (idntfyrefid int, gnrcitmid int);
create table other_ref(idntfyrefid int, catnmeclssid text, actvle text);

CREATE OR REPLACE VIEW test_view AS
SELECT or0.actvle AS treename
FROM gnrcitm g
LEFT JOIN (gnrcitmothrref g0
JOIN other_ref r0 ON g0.idntfyrefid = r0.idntfyrefid AND
r0.catnmeclssid::text = 'Tree Name'::text) or0
ON g.gnrcitmid = or0.gnrcitmid;

pg_get_viewdef(viewoid, true) will return

CREATE OR REPLACE VIEW test_view AS
SELECT or0.actvle AS treename
FROM gnrcitm g
LEFT JOIN
( -- <<<
(gnrcitmothrref g0
JOIN other_ref r0 ON g0.idntfyrefid = r0.idntfyrefid AND
r0.catnmeclssid = 'Tree Name'::text) or0
) -- <<<
ON g.gnrcitmid = or0.gnrcitmid;

The attached patch corrects this, without affecting the following:

CREATE OR REPLACE VIEW test_view2 AS
SELECT r0.actvle AS treename
FROM gnrcitm g
LEFT JOIN (gnrcitmothrref g0
JOIN other_ref r0 ON g0.idntfyrefid = r0.idntfyrefid AND
r0.catnmeclssid::text = 'Tree Name'::text)
ON g.gnrcitmid = g0.gnrcitmid

Regards,
Andreas