Fix NPE when listing directory; patch by yukim reviewed by jbellis for CASSANDRA-4572
Fix NPE when listing directory; patch by yukim reviewed by jbellis for
CASSANDRA-4572

pkdevbox/cassandra,jrwest/cassandra,lalithsuresh/cassandra-c3,spodkowinski/cassandra,helena/cassandra,sluk3r/cassandra,carlyeks/cassandra,LatencyUtils/cassandra-stress2,weipinghe/cassandra,yangzhe1991/cassandra,jasonstack/cassandra,mambocab/cassandra,heiko-braun/cassandra,taigetco/cassandra_read,pofallon/cassandra,vaibhi9/cassandra,hhorii/cassandra,michaelmior/cassandra,cooldoger/cassandra,scylladb/scylla-tools-java,belliottsmith/cassandra,macintoshio/cassandra,clohfink/cassandra,vramaswamy456/cassandra,adelapena/cassandra,Instagram/cassandra,spodkowinski/cassandra,jasobrown/cassandra,snazy/cassandra,xiongzheng/Cassandra-Research,dkua/cassandra,HidemotoNakada/cassandra-udf,tjake/cassandra,clohfink/cassandra,yukim/cassandra,michaelmior/cassandra,jrwest/cassandra,ejankan/cassandra,fengshao0907/cassandra-1,juiceblender/cassandra,blerer/cassandra,bdeggleston/cassandra,exoscale/cassandra,yonglehou/cassandra,aureagle/cassandra,yanbit/cassandra,adelapena/cassandra,josh-mckenzie/cassandra,Instagram/cassandra,regispl/cassandra,michaelmior/cassandra,chbatey/cassandra-1,bpupadhyaya/cassandra,bdeggleston/cassandra,whitepages/cassandra,spodkowinski/cassandra,apache/cassandra,pofallon/cassandra,tommystendahl/cassandra,driftx/cassandra,christian-esken/cassandra,sharvanath/cassandra,rogerchina/cassandra,blerer/cassandra,sayanh/ViewMaintenanceCassandra,shawnkumar/cstargraph,yonglehou/cassandra,newrelic-forks/cassandra,pthomaid/cassandra,fengshao0907/Cassandra-Research,MasahikoSawada/cassandra,nvoron23/cassandra,sriki77/cassandra,scaledata/cassandra,bcoverston/cassandra,guanxi55nba/key-value-store,mshuler/cassandra,ptnapoleon/cassandra,sivikt/cassandra,kgreav/cassandra,joesiewert/cassandra,clohfink/cassandra,thelastpickle/cassandra,emolsson/cassandra,matthewtt/cassandra_read,bcoverston/cassandra,yhnishi/cassandra,rdio/cassandra,vaibhi9/cassandra,jkni/cassandra,sharvanath/cassandra,asias/cassandra,miguel0afd/cassandra-cqlMod,Stratio/stratio-cassandra,newrelic-forks/cassandra,leomrocha/cassandra,pcn/cassandra-1,mkjellman/cassandra,jeromatron/cassandra,tongjixianing/projects,pauloricardomg/cassandra,likaiwalkman/cassandra,emolsson/cassandra,jbellis/cassandra,Bj0rnen/cassandra,apache/cassandra,ollie314/cassandra,pauloricardomg/cassandra,aboudreault/cassandra,mheffner/cassandra-1,DavidHerzogTU-Berlin/cassandraToRun,HidemotoNakada/cassandra-udf,leomrocha/cassandra,juiceblender/cassandra,Imran-C/cassandra,boneill42/cassandra,mkjellman/cassandra,mshuler/cassandra,jeffjirsa/cassandra,tjake/cassandra,DavidHerzogTU-Berlin/cassandra,belliottsmith/cassandra,stef1927/cassandra,Stratio/cassandra,snazy/cassandra,phact/cassandra,weideng1/cassandra,apache/cassandra,pcn/cassandra-1,likaiwalkman/cassandra,boneill42/cassandra,pcmanus/cassandra,project-zerus/cassandra,tongjixianing/projects,weipinghe/cassandra,driftx/cassandra,beobal/cassandra,bpupadhyaya/cassandra,pthomaid/cassandra,iamaleksey/cassandra,jasonwee/cassandra,beobal/cassandra,WorksApplications/cassandra,mheffner/cassandra-1,emolsson/cassandra,helena/cassandra,rmarchei/cassandra,chbatey/cassandra-1,sayanh/ViewMaintenanceCassandra,gdusbabek/cassandra,instaclustr/cassandra,heiko-braun/cassandra,weipinghe/cassandra,dprguiuc/Cassandra-Wasef,Stratio/cassandra,adelapena/cassandra,macintoshio/cassandra,dprguiuc/Cassandra-Wasef,likaiwalkman/cassandra,jasobrown/cassandra,rogerchina/cassandra,aweisberg/cassandra,jsanda/cassandra,pallavi510/cassandra,pauloricardomg/cassandra,pkdevbox/cassandra,sayanh/ViewMaintenanceSupport,michaelsembwever/cassandra,JeremiahDJordan/cassandra,kgreav/cassandra,scylladb/scylla-tools-java,thelastpickle/cassandra,pofallon/cassandra,yhnishi/cassandra,weideng1/cassandra,carlyeks/cassandra,driftx/cassandra,carlyeks/cassandra,sayanh/ViewMaintenanceSupport,dkua/cassandra,gdusbabek/cassandra,modempachev4/kassandra,mashuai/Cassandra-Research,dongjiaqiang/cassandra,Imran-C/cassandra,swps/cassandra,sriki77/cassandra,scylladb/scylla-tools-java,scaledata/cassandra,hengxin/cassandra,MasahikoSawada/cassandra,strapdata/cassandra,DavidHerzogTU-Berlin/cassandra,iamaleksey/cassandra,adejanovski/cassandra,instaclustr/cassandra,jasonstack/cassandra,mike-tr-adamson/cassandra,RyanMagnusson/cassandra,bmel/cassandra,Jollyplum/cassandra,nutbunnies/cassandra,Bj0rnen/cassandra,DavidHerzogTU-Berlin/cassandraToRun,darach/cassandra,caidongyun/cassandra,leomrocha/cassandra,dprguiuc/Cassandra-Wasef,DikangGu/cassandra,cooldoger/cassandra,a-buck/cassandra,thelastpickle/cassandra,dkua/cassandra,strapdata/cassandra,aureagle/cassandra,newrelic-forks/cassandra,thobbs/cassandra,ollie314/cassandra,Jaumo/cassandra,bpupadhyaya/cassandra,codefollower/Cassandra-Research,Stratio/cassandra,iamaleksey/cassandra,swps/cassandra,vramaswamy456/cassandra,krummas/cassandra,fengshao0907/cassandra-1,RyanMagnusson/cassandra,jeromatron/cassandra,ibmsoe/cassandra,ejankan/cassandra,pallavi510/cassandra,cooldoger/cassandra,knifewine/cassandra,ben-manes/cassandra,EnigmaCurry/cassandra,EnigmaCurry/cassandra,WorksApplications/cassandra,sbtourist/cassandra,boneill42/cassandra,thobbs/cassandra,jsanda/cassandra,GabrielNicolasAvellaneda/cassandra,belliottsmith/cassandra,Stratio/stratio-cassandra,phact/cassandra,spodkowinski/cassandra,Bj0rnen/cassandra,yanbit/cassandra,jbellis/cassandra,tongjixianing/projects,yangzhe1991/cassandra,caidongyun/cassandra,bcoverston/cassandra,rmarchei/cassandra,JeremiahDJordan/cassandra,codefollower/Cassandra-Research,strapdata/cassandra,qinjin/mdtc-cassandra,yanbit/cassandra,ifesdjeen/cassandra,adejanovski/cassandra,sayanh/ViewMaintenanceCassandra,mike-tr-adamson/cassandra,blambov/cassandra,modempachev4/kassandra,fengshao0907/cassandra-1,szhou1234/cassandra,EnigmaCurry/cassandra,hengxin/cassandra,vramaswamy456/cassandra,chaordic/cassandra,ben-manes/cassandra,ptuckey/cassandra,nakomis/cassandra,scylladb/scylla-tools-java,jkni/cassandra,codefollower/Cassandra-Research,JeremiahDJordan/cassandra,ollie314/cassandra,pcmanus/cassandra,knifewine/cassandra,blerer/cassandra,exoscale/cassandra,Stratio/stratio-cassandra,mike-tr-adamson/cassandra,lalithsuresh/cassandra-c3,nitsanw/cassandra,miguel0afd/cassandra-cqlMod,nitsanw/cassandra,nvoron23/cassandra,a-buck/cassandra,mt0803/cassandra,hhorii/cassandra,nutbunnies/cassandra,tjake/cassandra,WorksApplications/cassandra,hengxin/cassandra,blerer/cassandra,aureagle/cassandra,ibmsoe/cassandra,thobbs/cassandra,guard163/cassandra,asias/cassandra,xiongzheng/Cassandra-Research,mt0803/cassandra,krummas/cassandra,aweisberg/cassandra,matthewtt/cassandra_read,tommystendahl/cassandra,wreda/cassandra,guanxi55nba/key-value-store,yhnishi/cassandra,xiongzheng/Cassandra-Research,sedulam/CASSANDRA-12201,iburmistrov/Cassandra,heiko-braun/cassandra,kangkot/stratio-cassandra,wreda/cassandra,hhorii/cassandra,aboudreault/cassandra,WorksApplications/cassandra,rdio/cassandra,mgmuscari/cassandra-cdh4,kangkot/stratio-cassandra,cooldoger/cassandra,tjake/cassandra,yukim/cassandra,mt0803/cassandra,AtwooTM/cassandra,taigetco/cassandra_read,ptnapoleon/cassandra,pcn/cassandra-1,sriki77/cassandra,nakomis/cassandra,mambocab/cassandra,mambocab/cassandra,chbatey/cassandra-1,qinjin/mdtc-cassandra,pkdevbox/cassandra,adelapena/cassandra,yangzhe1991/cassandra,HidemotoNakada/cassandra-udf,knifewine/cassandra,bdeggleston/cassandra,ejankan/cassandra,sbtourist/cassandra,yukim/cassandra,swps/cassandra,jkni/cassandra,nlalevee/cassandra,rogerchina/cassandra,LatencyUtils/cassandra-stress2,aarushi12002/cassandra,clohfink/cassandra,tommystendahl/cassandra,jsanda/cassandra,bcoverston/cassandra,shawnkumar/cstargraph,fengshao0907/Cassandra-Research,christian-esken/cassandra,mike-tr-adamson/cassandra,DICL/cassandra,stef1927/cassandra,DavidHerzogTU-Berlin/cassandraToRun,macintoshio/cassandra,Jaumo/cassandra,miguel0afd/cassandra-cqlMod,project-zerus/cassandra,nvoron23/cassandra,jeromatron/cassandra,nlalevee/cassandra,aweisberg/cassandra,szhou1234/cassandra,ifesdjeen/cassandra,yonglehou/cassandra,joesiewert/cassandra,AtwooTM/cassandra,matthewtt/cassandra_read,nutbunnies/cassandra,kangkot/stratio-cassandra,jeffjirsa/cassandra,Instagram/cassandra,ben-manes/cassandra,yukim/cassandra,ptuckey/cassandra,sluk3r/cassandra,scaledata/cassandra,jeffjirsa/cassandra,ifesdjeen/cassandra,regispl/cassandra,bmel/cassandra,snazy/cassandra,kangkot/stratio-cassandra,rackerlabs/cloudmetrics-cassandra,strapdata/cassandra,DICL/cassandra,mashuai/Cassandra-Research,blambov/cassandra,instaclustr/cassandra,bmel/cassandra,exoscale/cassandra,rmarchei/cassandra,Stratio/stratio-cassandra,mkjellman/cassandra,mshuler/cassandra,josh-mckenzie/cassandra,regispl/cassandra,DICL/cassandra,juiceblender/cassandra,darach/cassandra,iburmistrov/Cassandra,apache/cassandra,josh-mckenzie/cassandra,AtwooTM/cassandra,nlalevee/cassandra,michaelsembwever/cassandra,mshuler/cassandra,weideng1/cassandra,pcmanus/cassandra,phact/cassandra,aboudreault/cassandra,whitepages/cassandra,sluk3r/cassandra,LatencyUtils/cassandra-stress2,blambov/cassandra,chaordic/cassandra,gdusbabek/cassandra,iamaleksey/cassandra,Jollyplum/cassandra,kangkot/stratio-cassandra,rackerlabs/cloudmetrics-cassandra,thelastpickle/cassandra,GabrielNicolasAvellaneda/cassandra,MasahikoSawada/cassandra,ptuckey/cassandra,joesiewert/cassandra,DavidHerzogTU-Berlin/cassandra,wreda/cassandra,szhou1234/cassandra,helena/cassandra,aweisberg/cassandra,Jollyplum/cassandra,fengshao0907/Cassandra-Research,vaibhi9/cassandra,mgmuscari/cassandra-cdh4,guard163/cassandra,mkjellman/cassandra,michaelsembwever/cassandra,darach/cassandra,krummas/cassandra,jeffjirsa/cassandra,jasobrown/cassandra,shawnkumar/cstargraph,guard163/cassandra,beobal/cassandra,guanxi55nba/db-improvement,szhou1234/cassandra,nitsanw/cassandra,snazy/cassandra,bcoverston/apache-hosted-cassandra,ifesdjeen/cassandra,mgmuscari/cassandra-cdh4,bcoverston/apache-hosted-cassandra,guanxi55nba/db-improvement,Jaumo/cassandra,beobal/cassandra,nakomis/cassandra,qinjin/mdtc-cassandra,jasobrown/cassandra,sedulam/CASSANDRA-12201,sedulam/CASSANDRA-12201,jasonstack/cassandra,christian-esken/cassandra,modempachev4/kassandra,asias/cassandra,kgreav/cassandra,driftx/cassandra,jasonwee/cassandra,project-zerus/cassandra,pauloricardomg/cassandra,pallavi510/cassandra,jrwest/cassandra,a-buck/cassandra,rackerlabs/cloudmetrics-cassandra,RyanMagnusson/cassandra,aarushi12002/cassandra,rdio/cassandra,sbtourist/cassandra,jbellis/cassandra,jasonwee/cassandra,juiceblender/cassandra,michaelsembwever/cassandra,krummas/cassandra,guanxi55nba/key-value-store,dongjiaqiang/cassandra,pthomaid/cassandra,blambov/cassandra,guanxi55nba/db-improvement,tommystendahl/cassandra,adejanovski/cassandra,ibmsoe/cassandra,taigetco/cassandra_read,DikangGu/cassandra,sivikt/cassandra,mashuai/Cassandra-Research,ptnapoleon/cassandra,stef1927/cassandra,sharvanath/cassandra,whitepages/cassandra,aarushi12002/cassandra,kgreav/cassandra,jrwest/cassandra,dongjiaqiang/cassandra,chaordic/cassandra,iburmistrov/Cassandra,stef1927/cassandra,DikangGu/cassandra,bdeggleston/cassandra,belliottsmith/cassandra,Instagram/cassandra,instaclustr/cassandra,lalithsuresh/cassandra-c3,Imran-C/cassandra,bcoverston/apache-hosted-cassandra,josh-mckenzie/cassandra,sivikt/cassandra,caidongyun/cassandra,Stratio/stratio-cassandra,mheffner/cassandra-1,GabrielNicolasAvellaneda/cassandra