HashLinkedList::Iterator: remove an ununsed class variable
HashLinkedList::Iterator: remove an ununsed class variable

Summary: This variable is not used. Remove it.

Test Plan: build.

Reviewers: haobo, igor, yhchiang

Reviewed By: haobo

CC: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18525

temicai/rocksdb,Andymic/rocksdb,rDSN-Projects/rocksdb.replicated,SunguckLee/RocksDB,Applied-Duality/rocksdb,wat-ze-hex/rocksdb,msb-at-yahoo/rocksdb,luckywhu/rocksdb,temicai/rocksdb,lgscofield/rocksdb,jalexanderqed/rocksdb,dkorolev/rocksdb,tsheasha/rocksdb,NickCis/rocksdb,hobinyoon/rocksdb,Vaisman/rocksdb,virtdb/rocksdb,vmx/rocksdb,jalexanderqed/rocksdb,norton/rocksdb,wat-ze-hex/rocksdb,Andymic/rocksdb,ryneli/rocksdb,wlqGit/rocksdb,vmx/rocksdb,wenduo/rocksdb,lgscofield/rocksdb,biddyweb/rocksdb,siddhartharay007/rocksdb,mbarbon/rocksdb,wlqGit/rocksdb,geraldoandradee/rocksdb,anagav/rocksdb,kaschaeffer/rocksdb,OverlordQ/rocksdb,JackLian/rocksdb,JackLian/rocksdb,bbiao/rocksdb,luckywhu/rocksdb,norton/rocksdb,sorphi/rocksdb,msb-at-yahoo/rocksdb,wlqGit/rocksdb,dkorolev/rocksdb,wskplho/rocksdb,amyvmiwei/rocksdb,amyvmiwei/rocksdb,caijieming-baidu/rocksdb,temicai/rocksdb,NickCis/rocksdb,anagav/rocksdb,tizzybec/rocksdb,tizzybec/rocksdb,dkorolev/rocksdb,temicai/rocksdb,RyanTech/rocksdb,ylong/rocksdb,IMCG/RcoksDB,ryneli/rocksdb,luckywhu/rocksdb,bbiao/rocksdb,mbarbon/rocksdb,kaschaeffer/rocksdb,norton/rocksdb,Applied-Duality/rocksdb,alihalabyah/rocksdb,mbarbon/rocksdb,makelivedotnet/rocksdb,vmx/rocksdb,mbarbon/rocksdb,JoeWoo/rocksdb,biddyweb/rocksdb,Applied-Duality/rocksdb,kaschaeffer/rocksdb,tsheasha/rocksdb,vashstorm/rocksdb,lgscofield/rocksdb,tizzybec/rocksdb,rDSN-Projects/rocksdb.replicated,lgscofield/rocksdb,siddhartharay007/rocksdb,rDSN-Projects/rocksdb.replicated,bbiao/rocksdb,siddhartharay007/rocksdb,tschottdorf/rocksdb,zhangpng/rocksdb,JohnPJenkins/rocksdb,kaschaeffer/rocksdb,alihalabyah/rocksdb,dkorolev/rocksdb,caijieming-baidu/rocksdb,wat-ze-hex/rocksdb,biddyweb/rocksdb,sorphi/rocksdb,fengshao0907/rocksdb,mbarbon/rocksdb,alihalabyah/rocksdb,sorphi/rocksdb,SunguckLee/RocksDB,Vaisman/rocksdb,wskplho/rocksdb,luckywhu/rocksdb,geraldoandradee/rocksdb,biddyweb/rocksdb,tizzybec/rocksdb,vashstorm/rocksdb,facebook/rocksdb,IMCG/RcoksDB,virtdb/rocksdb,Vaisman/rocksdb,geraldoandradee/rocksdb,makelivedotnet/rocksdb,wskplho/rocksdb,kaschaeffer/rocksdb,geraldoandradee/rocksdb,tizzybec/rocksdb,Andymic/rocksdb,norton/rocksdb,siddhartharay007/rocksdb,sorphi/rocksdb,vmx/rocksdb,wlqGit/rocksdb,hobinyoon/rocksdb,RyanTech/rocksdb,skunkwerks/rocksdb,IMCG/RcoksDB,mbarbon/rocksdb,wskplho/rocksdb,Andymic/rocksdb,JoeWoo/rocksdb,fengshao0907/rocksdb,dkorolev/rocksdb,tschottdorf/rocksdb,RyanTech/rocksdb,jalexanderqed/rocksdb,JackLian/rocksdb,msb-at-yahoo/rocksdb,fengshao0907/rocksdb,wat-ze-hex/rocksdb,norton/rocksdb,Andymic/rocksdb,tschottdorf/rocksdb,JackLian/rocksdb,vashstorm/rocksdb,vashstorm/rocksdb,siddhartharay007/rocksdb,JoeWoo/rocksdb,geraldoandradee/rocksdb,kaschaeffer/rocksdb,Andymic/rocksdb,wskplho/rocksdb,fengshao0907/rocksdb,lgscofield/rocksdb,tsheasha/rocksdb,vmx/rocksdb,hobinyoon/rocksdb,virtdb/rocksdb,vmx/rocksdb,wenduo/rocksdb,rDSN-Projects/rocksdb.replicated,caijieming-baidu/rocksdb,zhangpng/rocksdb,facebook/rocksdb,SunguckLee/RocksDB,facebook/rocksdb,zhangpng/rocksdb,zhangpng/rocksdb,tschottdorf/rocksdb,sorphi/rocksdb,flabby/rocksdb,bbiao/rocksdb,bbiao/rocksdb,JackLian/rocksdb,tsheasha/rocksdb,hobinyoon/rocksdb,skunkwerks/rocksdb,wenduo/rocksdb,fengshao0907/rocksdb,NickCis/rocksdb,hobinyoon/rocksdb,facebook/rocksdb,OverlordQ/rocksdb,luckywhu/rocksdb,msb-at-yahoo/rocksdb,NickCis/rocksdb,ylong/rocksdb,facebook/rocksdb,amyvmiwei/rocksdb,luckywhu/rocksdb,SunguckLee/RocksDB,virtdb/rocksdb,JohnPJenkins/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,ryneli/rocksdb,virtdb/rocksdb,amyvmiwei/rocksdb,tschottdorf/rocksdb,facebook/rocksdb,hobinyoon/rocksdb,bbiao/rocksdb,amyvmiwei/rocksdb,makelivedotnet/rocksdb,biddyweb/rocksdb,Applied-Duality/rocksdb,wat-ze-hex/rocksdb,NickCis/rocksdb,ylong/rocksdb,vmx/rocksdb,tizzybec/rocksdb,vashstorm/rocksdb,ylong/rocksdb,Applied-Duality/rocksdb,siddhartharay007/rocksdb,msb-at-yahoo/rocksdb,wenduo/rocksdb,SunguckLee/RocksDB,alihalabyah/rocksdb,lgscofield/rocksdb,ryneli/rocksdb,IMCG/RcoksDB,flabby/rocksdb,flabby/rocksdb,zhangpng/rocksdb,vashstorm/rocksdb,OverlordQ/rocksdb,temicai/rocksdb,norton/rocksdb,geraldoandradee/rocksdb,Vaisman/rocksdb,flabby/rocksdb,biddyweb/rocksdb,temicai/rocksdb,makelivedotnet/rocksdb,Vaisman/rocksdb,jalexanderqed/rocksdb,luckywhu/rocksdb,flabby/rocksdb,tsheasha/rocksdb,makelivedotnet/rocksdb,norton/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,Andymic/rocksdb,IMCG/RcoksDB,biddyweb/rocksdb,caijieming-baidu/rocksdb,jalexanderqed/rocksdb,kaschaeffer/rocksdb,wlqGit/rocksdb,geraldoandradee/rocksdb,skunkwerks/rocksdb,rDSN-Projects/rocksdb.replicated,skunkwerks/rocksdb,OverlordQ/rocksdb,norton/rocksdb,dkorolev/rocksdb,virtdb/rocksdb,skunkwerks/rocksdb,siddhartharay007/rocksdb,temicai/rocksdb,JoeWoo/rocksdb,JohnPJenkins/rocksdb,ylong/rocksdb,fengshao0907/rocksdb,hobinyoon/rocksdb,anagav/rocksdb,tsheasha/rocksdb,anagav/rocksdb,alihalabyah/rocksdb,wskplho/rocksdb,skunkwerks/rocksdb,JoeWoo/rocksdb,facebook/rocksdb,RyanTech/rocksdb,Andymic/rocksdb,wat-ze-hex/rocksdb,makelivedotnet/rocksdb,wlqGit/rocksdb,ryneli/rocksdb,vmx/rocksdb,alihalabyah/rocksdb,wlqGit/rocksdb,JackLian/rocksdb,amyvmiwei/rocksdb,wenduo/rocksdb,JohnPJenkins/rocksdb,jalexanderqed/rocksdb,ylong/rocksdb,NickCis/rocksdb,alihalabyah/rocksdb,skunkwerks/rocksdb,wat-ze-hex/rocksdb,wskplho/rocksdb,RyanTech/rocksdb,NickCis/rocksdb,Vaisman/rocksdb,JoeWoo/rocksdb,wenduo/rocksdb,tschottdorf/rocksdb,IMCG/RcoksDB,Applied-Duality/rocksdb,ylong/rocksdb,flabby/rocksdb,hobinyoon/rocksdb,IMCG/RcoksDB,fengshao0907/rocksdb,bbiao/rocksdb,tizzybec/rocksdb,amyvmiwei/rocksdb,tsheasha/rocksdb,anagav/rocksdb,wat-ze-hex/rocksdb,flabby/rocksdb,JohnPJenkins/rocksdb,sorphi/rocksdb,wenduo/rocksdb,ryneli/rocksdb,ryneli/rocksdb,JohnPJenkins/rocksdb,bbiao/rocksdb,vashstorm/rocksdb,wenduo/rocksdb,rDSN-Projects/rocksdb.replicated,RyanTech/rocksdb,caijieming-baidu/rocksdb,Applied-Duality/rocksdb,anagav/rocksdb,msb-at-yahoo/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,sorphi/rocksdb,RyanTech/rocksdb,makelivedotnet/rocksdb,virtdb/rocksdb,caijieming-baidu/rocksdb,dkorolev/rocksdb,rDSN-Projects/rocksdb.replicated,zhangpng/rocksdb,lgscofield/rocksdb,JohnPJenkins/rocksdb,jalexanderqed/rocksdb,tsheasha/rocksdb,zhangpng/rocksdb,JoeWoo/rocksdb,caijieming-baidu/rocksdb,mbarbon/rocksdb,facebook/rocksdb,anagav/rocksdb,JackLian/rocksdb,Vaisman/rocksdb