Log Message:
-----------
Allow planner to fold "stable" functions to constants when forming
selectivity estimates, per recent discussion.
Modified Files:
--------------
pgsql/src/backend/optimizer/util:
clauses.c (r1.183 -> r1.184)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/clauses.c.diff?r1=1.183&r2=1.184)