Fix assertion failure from calling contain_agg_clause on raw parse tree
Fix assertion failure from calling contain_agg_clause on raw parse tree

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adam8157/gpdb,50wu/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,edespino/gpdb,50wu/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,yuanzhao/gpdb,adam8157/gpdb,lisakowen/gpdb,jmcatamney/gpdb,xinzweb/gpdb,lisakowen/gpdb,yuanzhao/gpdb,lisakowen/gpdb,edespino/gpdb,edespino/gpdb,adam8157/gpdb,Chibin/gpdb,Chibin/gpdb,lisakowen/gpdb,xinzweb/gpdb,yuanzhao/gpdb,50wu/gpdb,lisakowen/gpdb,greenplum-db/gpdb,lisakowen/gpdb,adam8157/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,50wu/gpdb,lisakowen/gpdb,Chibin/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,lisakowen/gpdb,50wu/gpdb,greenplum-db/gpdb,yuanzhao/gpdb,ashwinstar/gpdb,edespino/gpdb,greenplum-db/gpdb,adam8157/gpdb,Chibin/gpdb,edespino/gpdb,xinzweb/gpdb,jmcatamney/gpdb,xinzweb/gpdb,edespino/gpdb,ashwinstar/gpdb,edespino/gpdb,50wu/gpdb,edespino/gpdb,greenplum-db/gpdb,edespino/gpdb,edespino/gpdb,50wu/gpdb,jmcatamney/gpdb,xinzweb/gpdb,ashwinstar/gpdb,adam8157/gpdb,Chibin/gpdb,50wu/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,Chibin/gpdb,ashwinstar/gpdb,yuanzhao/gpdb,yuanzhao/gpdb,yuanzhao/gpdb,adam8157/gpdb,yuanzhao/gpdb,yuanzhao/gpdb,xinzweb/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,Chibin/gpdb,Chibin/gpdb,Chibin/gpdb,Chibin/gpdb,adam8157/gpdb,xinzweb/gpdb,xinzweb/gpdb,yuanzhao/gpdb