Log Message:
-----------
timestamptz_izone should return the input, not NULL, when the input
is a non-finite timestamp, for consistency with related functions.
In other words: +infinity rotated to a different timezone is still
+infinity.
Modified Files:
--------------
pgsql/src/backend/utils/adt:
timestamp.c (r1.152 -> r1.153)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/timestamp.c.diff?r1=1.152&r2=1.153)