Fixed two bugs on logging file deletion.
Fixed two bugs on logging file deletion.

Summary:
This patch fixes the following two bugs on logging file deletion.

1.  Previously, file deletion failure was only logged in INFO_LEVEL.
    This patch changes it to ERROR_LEVEL and does some code clean.

2.  EventLogger previously will always generate the same log on
    table file deletion even when file deletion is not successful.
    Now the resulting status of file deletion will also be logged.

Test Plan: make all check

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38817

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