Log Message:
-----------
Defend against null input in analyze_requires_snapshot(), per report
from Rushabh Lathia.
Modified Files:
--------------
pgsql/src/backend/parser:
analyze.c (r1.386 -> r1.387)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/analyze.c?r1=1.386&r2=1.387)