Fix qual_is_pushdown_safe to not try to push down quals involving a whole-row Var referencing the subselect output.  While this case could possibly be made to work, it seems not worth expending effort on.  Per report from Magnus Naeslund(f).
Fix qual_is_pushdown_safe to not try to push down quals involving a whole-row
Var referencing the subselect output.  While this case could possibly be made
to work, it seems not worth expending effort on.  Per report from Magnus
Naeslund(f).

yuanzhao/gpdb,zeroae/postgres-xl,snaga/postgres-xl,lintzc/gpdb,CraigHarris/gpdb,rubikloud/gpdb,ashwinstar/gpdb,Postgres-XL/Postgres-XL,tangp3/gpdb,CraigHarris/gpdb,foyzur/gpdb,chrishajas/gpdb,Postgres-XL/Postgres-XL,greenplum-db/gpdb,0x0FFF/gpdb,Quikling/gpdb,chrishajas/gpdb,xinzweb/gpdb,cjcjameson/gpdb,lisakowen/gpdb,chrishajas/gpdb,techdragon/Postgres-XL,zeroae/postgres-xl,Quikling/gpdb,kaknikhil/gpdb,janebeckman/gpdb,tangp3/gpdb,adam8157/gpdb,janebeckman/gpdb,xuegang/gpdb,0x0FFF/gpdb,xuegang/gpdb,pavanvd/postgres-xl,rubikloud/gpdb,CraigHarris/gpdb,xinzweb/gpdb,postmind-net/postgres-xl,lintzc/gpdb,lisakowen/gpdb,yuanzhao/gpdb,lintzc/gpdb,greenplum-db/gpdb,ovr/postgres-xl,edespino/gpdb,jmcatamney/gpdb,Quikling/gpdb,kaknikhil/gpdb,techdragon/Postgres-XL,yazun/postgres-xl,greenplum-db/gpdb,janebeckman/gpdb,ashwinstar/gpdb,CraigHarris/gpdb,zaksoup/gpdb,foyzur/gpdb,ashwinstar/gpdb,adam8157/gpdb,Quikling/gpdb,atris/gpdb,lpetrov-pivotal/gpdb,tangp3/gpdb,yazun/postgres-xl,ovr/postgres-xl,greenplum-db/gpdb,50wu/gpdb,arcivanov/postgres-xl,zeroae/postgres-xl,techdragon/Postgres-XL,Chibin/gpdb,royc1/gpdb,janebeckman/gpdb,yuanzhao/gpdb,tpostgres-projects/tPostgres,lisakowen/gpdb,pavanvd/postgres-xl,randomtask1155/gpdb,royc1/gpdb,foyzur/gpdb,kmjungersen/PostgresXL,jmcatamney/gpdb,pavanvd/postgres-xl,lpetrov-pivotal/gpdb,lisakowen/gpdb,yazun/postgres-xl,xinzweb/gpdb,xuegang/gpdb,randomtask1155/gpdb,chrishajas/gpdb,yazun/postgres-xl,50wu/gpdb,xinzweb/gpdb,chrishajas/gpdb,atris/gpdb,kaknikhil/gpdb,rvs/gpdb,jmcatamney/gpdb,0x0FFF/gpdb,xinzweb/gpdb,50wu/gpdb,xinzweb/gpdb,janebeckman/gpdb,janebeckman/gpdb,Chibin/gpdb,tangp3/gpdb,randomtask1155/gpdb,adam8157/gpdb,Quikling/gpdb,zeroae/postgres-xl,edespino/gpdb,adam8157/gpdb,zaksoup/gpdb,atris/gpdb,rubikloud/gpdb,Chibin/gpdb,oberstet/postgres-xl,yuanzhao/gpdb,yuanzhao/gpdb,Postgres-XL/Postgres-XL,atris/gpdb,edespino/gpdb,lpetrov-pivotal/gpdb,arcivanov/postgres-xl,0x0FFF/gpdb,postmind-net/postgres-xl,oberstet/postgres-xl,cjcjameson/gpdb,kaknikhil/gpdb,zaksoup/gpdb,randomtask1155/gpdb,Chibin/gpdb,snaga/postgres-xl,randomtask1155/gpdb,royc1/gpdb,lpetrov-pivotal/gpdb,adam8157/gpdb,janebeckman/gpdb,postmind-net/postgres-xl,yuanzhao/gpdb,arcivanov/postgres-xl,ashwinstar/gpdb,50wu/gpdb,lisakowen/gpdb,cjcjameson/gpdb,edespino/gpdb,cjcjameson/gpdb,rvs/gpdb,ahachete/gpdb,atris/gpdb,chrishajas/gpdb,cjcjameson/gpdb,Quikling/gpdb,tpostgres-projects/tPostgres,Quikling/gpdb,lpetrov-pivotal/gpdb,rubikloud/gpdb,edespino/gpdb,zaksoup/gpdb,50wu/gpdb,jmcatamney/gpdb,edespino/gpdb,atris/gpdb,rubikloud/gpdb,ashwinstar/gpdb,rvs/gpdb,lintzc/gpdb,0x0FFF/gpdb,tpostgres-projects/tPostgres,janebeckman/gpdb,jmcatamney/gpdb,kaknikhil/gpdb,greenplum-db/gpdb,ahachete/gpdb,xuegang/gpdb,cjcjameson/gpdb,tangp3/gpdb,CraigHarris/gpdb,kaknikhil/gpdb,kaknikhil/gpdb,royc1/gpdb,kmjungersen/PostgresXL,kaknikhil/gpdb,ashwinstar/gpdb,oberstet/postgres-xl,zaksoup/gpdb,lintzc/gpdb,atris/gpdb,foyzur/gpdb,rvs/gpdb,zaksoup/gpdb,lintzc/gpdb,greenplum-db/gpdb,tpostgres-projects/tPostgres,lintzc/gpdb,Chibin/gpdb,arcivanov/postgres-xl,snaga/postgres-xl,foyzur/gpdb,cjcjameson/gpdb,randomtask1155/gpdb,rvs/gpdb,Chibin/gpdb,chrishajas/gpdb,foyzur/gpdb,Postgres-XL/Postgres-XL,techdragon/Postgres-XL,ahachete/gpdb,cjcjameson/gpdb,Quikling/gpdb,edespino/gpdb,lintzc/gpdb,adam8157/gpdb,Quikling/gpdb,ashwinstar/gpdb,lpetrov-pivotal/gpdb,tpostgres-projects/tPostgres,randomtask1155/gpdb,zaksoup/gpdb,janebeckman/gpdb,ahachete/gpdb,yuanzhao/gpdb,0x0FFF/gpdb,jmcatamney/gpdb,atris/gpdb,xuegang/gpdb,adam8157/gpdb,ahachete/gpdb,yuanzhao/gpdb,xuegang/gpdb,kmjungersen/PostgresXL,greenplum-db/gpdb,xinzweb/gpdb,rubikloud/gpdb,Postgres-XL/Postgres-XL,techdragon/Postgres-XL,rvs/gpdb,CraigHarris/gpdb,kaknikhil/gpdb,0x0FFF/gpdb,rvs/gpdb,rvs/gpdb,edespino/gpdb,cjcjameson/gpdb,lintzc/gpdb,edespino/gpdb,royc1/gpdb,greenplum-db/gpdb,postmind-net/postgres-xl,royc1/gpdb,rvs/gpdb,ovr/postgres-xl,lpetrov-pivotal/gpdb,pavanvd/postgres-xl,janebeckman/gpdb,ahachete/gpdb,edespino/gpdb,50wu/gpdb,tangp3/gpdb,oberstet/postgres-xl,0x0FFF/gpdb,Chibin/gpdb,kaknikhil/gpdb,lisakowen/gpdb,xuegang/gpdb,lpetrov-pivotal/gpdb,50wu/gpdb,xinzweb/gpdb,randomtask1155/gpdb,jmcatamney/gpdb,zeroae/postgres-xl,ovr/postgres-xl,kmjungersen/PostgresXL,xuegang/gpdb,arcivanov/postgres-xl,snaga/postgres-xl,arcivanov/postgres-xl,foyzur/gpdb,rvs/gpdb,chrishajas/gpdb,yuanzhao/gpdb,lisakowen/gpdb,Chibin/gpdb,CraigHarris/gpdb,50wu/gpdb,ahachete/gpdb,rubikloud/gpdb,oberstet/postgres-xl,royc1/gpdb,ahachete/gpdb,adam8157/gpdb,kmjungersen/PostgresXL,postmind-net/postgres-xl,rubikloud/gpdb,CraigHarris/gpdb,xuegang/gpdb,yuanzhao/gpdb,tangp3/gpdb,pavanvd/postgres-xl,Chibin/gpdb,snaga/postgres-xl,ashwinstar/gpdb,foyzur/gpdb,CraigHarris/gpdb,jmcatamney/gpdb,tangp3/gpdb,Chibin/gpdb,Quikling/gpdb,lisakowen/gpdb,yazun/postgres-xl,cjcjameson/gpdb,zaksoup/gpdb,royc1/gpdb,ovr/postgres-xl