Also remove WindowSpecParse.
Also remove WindowSpecParse.

I meant to remove this in previous commit already, but forgot to "git add".

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