pgsql: Add code to eval_const_expressions() to support - Mailing list pgsql-committers

Log Message:
-----------
Add code to eval_const_expressions() to support const-simplification of
CoerceViaIO nodes.  This improves the ability of the planner to deal with
cases where the node input is a constant.  Per bug #4170.

Modified Files:
--------------
    pgsql/src/backend/optimizer/util:
        clauses.c (r1.258 -> r1.259)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/clauses.c?r1=1.258&r2=1.259)