pgsql: array_map failed to insert correct result type in an empty array.

Log Message:
-----------
array_map failed to insert correct result type in an empty array.
Per example from Florian Pflug.

Tags:
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REL7_3_STABLE

Modified Files:
--------------
pgsql/src/backend/utils/adt:
arrayfuncs.c (r1.81 -> r1.81.2.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/arrayfuncs.c.diff?r1=1.81&r2=1.81.2.1)