fix #3553: legacy copy_slice_to (#3564)
fix #3553: legacy copy_slice_to (#3564)

* fix #3553: legacy copy_slice_to

* fix lint errors

szha/mxnet,EvanzzzZ/mxnet,indhub/mxnet,dmlc/mxnet,hesseltuinhof/mxnet,mbaijal/incubator-mxnet,jermainewang/mxnet,stefanhenneking/mxnet,luoyetx/mxnet,gautamkmr/incubator-mxnet,apaleyes/mxnet,weleen/mxnet,gautamkmr/incubator-mxnet,Mega-DatA-Lab/mxnet,kevinthesun/mxnet,pluskid/mxnet,thirdwing/mxnet,jamesliu/mxnet,jennyzhang0215/incubator-mxnet,coder-james/mxnet,szha/mxnet,Mega-DatA-Lab/mxnet,crazy-cat/incubator-mxnet,zhreshold/mxnet,ZihengJiang/mxnet,rahul003/mxnet,weleen/mxnet,kkk669/mxnet,nicklhy/mxnet,smolix/incubator-mxnet,indhub/mxnet,xcgoner/dist-mxnet,Prasad9/incubator-mxnet,danithaca/mxnet,ykim362/mxnet,weleen/mxnet,kkk669/mxnet,luoyetx/mxnet,coder-james/mxnet,arikpoz/mxnet,ykim362/mxnet,yuruofeifei/mxnet,kevinthesun/mxnet,fullfanta/mxnet,gautamkmr/incubator-mxnet,dmlc/mxnet,larroy/mxnet,zhreshold/mxnet,hotpxl/mxnet,navrasio/mxnet,hpi-xnor/BMXNet,ykim362/mxnet,antoan2/incubator-mxnet,sxjscience/mxnet,arikpoz/mxnet,saurabh3949/mxnet,danithaca/mxnet,sergeykolychev/mxnet,jiajiechen/mxnet,pluskid/mxnet,thirdwing/mxnet,reminisce/mxnet,piiswrong/mxnet,pluskid/mxnet,gautamkmr/incubator-mxnet,jamesliu/mxnet,wangyum/mxnet,sxjscience/mxnet,ptrendx/mxnet,tlby/mxnet,jiajiechen/mxnet,hotpxl/mxnet,hpi-xnor/BMXNet,sxjscience/mxnet,likelyzhao/mxnet,hesseltuinhof/mxnet,LinkHS/incubator-mxnet,CodingCat/mxnet,likelyzhao/mxnet,ykim362/mxnet,vikingMei/mxnet,precedenceguo/mxnet,rishita/mxnet,luoyetx/mxnet,danithaca/mxnet,sergeykolychev/mxnet,mbaijal/incubator-mxnet,eric-haibin-lin/mxnet,leezu/mxnet,dmlc/mxnet,madjam/mxnet,ForkedReposBak/mxnet,precedenceguo/mxnet,Northrend/mxnet,EvanzzzZ/mxnet,Guneet-Dhillon/mxnet,yuruofeifei/mxnet,precedenceguo/mxnet,larroy/mxnet,leezu/mxnet,saurabh3949/mxnet,sergeykolychev/mxnet,larroy/mxnet,vikingMei/mxnet,sxjscience/mxnet,rahul003/mxnet,hotpxl/mxnet,ShownX/incubator-mxnet,arank/mxnet,jiajiechen/mxnet,hotpxl/mxnet,TuSimple/mxnet,zhreshold/mxnet,leezu/mxnet,jermainewang/mxnet,apache/incubator-mxnet,tornadomeet/mxnet,kevinthesun/mxnet,apaleyes/mxnet,Ldpe2G/mxnet,solin319/incubator-mxnet,madjam/mxnet,zhreshold/mxnet,luoyetx/mxnet,eric-haibin-lin/mxnet,smolix/incubator-mxnet,navrasio/mxnet,madjam/mxnet,indhub/mxnet,Ldpe2G/mxnet,TuSimple/mxnet,likelyzhao/mxnet,LinkHS/incubator-mxnet,arank/mxnet,coder-james/mxnet,antoan2/incubator-mxnet,jamesliu/mxnet,wangyum/mxnet,zhreshold/mxnet,crazy-cat/incubator-mxnet,larroy/mxnet,Guneet-Dhillon/mxnet,arikpoz/mxnet,wangyum/mxnet,rishita/mxnet,Ldpe2G/mxnet,jermainewang/mxnet,Guneet-Dhillon/mxnet,tornadomeet/mxnet,saurabh3949/mxnet,danithaca/mxnet,hesseltuinhof/mxnet,LinkHS/incubator-mxnet,jennyzhang0215/incubator-mxnet,stefanhenneking/mxnet,apaleyes/mxnet,kevinthesun/mxnet,leezu/mxnet,jermainewang/mxnet,indhub/mxnet,szha/mxnet,ZihengJiang/mxnet,ForkedReposBak/mxnet,precedenceguo/mxnet,reminisce/mxnet,hesseltuinhof/mxnet,Prasad9/incubator-mxnet,thirdwing/mxnet,formath/mxnet,kevinthesun/mxnet,jamesliu/mxnet,nicklhy/mxnet,kkk669/mxnet,Northrend/mxnet,tlby/mxnet,TuSimple/mxnet,DR08/mxnet,Northrend/mxnet,LinkHS/incubator-mxnet,EvanzzzZ/mxnet,dmlc/mxnet,DickJC123/mxnet,weleen/mxnet,EvanzzzZ/mxnet,ShownX/incubator-mxnet,Ldpe2G/mxnet,crazy-cat/incubator-mxnet,eric-haibin-lin/mxnet,szha/mxnet,dmlc/mxnet,CodingCat/mxnet,EvanzzzZ/mxnet,fullfanta/mxnet,apache/incubator-mxnet,nicklhy/mxnet,wangyum/mxnet,rahul003/mxnet,danithaca/mxnet,jamesliu/mxnet,sergeykolychev/mxnet,Northrend/mxnet,DR08/mxnet,apaleyes/mxnet,tornadomeet/mxnet,hpi-xnor/BMXNet,rahul003/mxnet,danithaca/mxnet,yajiedesign/mxnet,nicklhy/mxnet,jiajiechen/mxnet,tlby/mxnet,apaleyes/mxnet,precedenceguo/mxnet,luoyetx/mxnet,antoan2/incubator-mxnet,ZihengJiang/mxnet,indhub/mxnet,rahul003/mxnet,eric-haibin-lin/mxnet,mbaijal/incubator-mxnet,likelyzhao/mxnet,ykim362/mxnet,ShownX/incubator-mxnet,yuruofeifei/mxnet,lxn2/mxnet,jermainewang/mxnet,lxn2/mxnet,xcgoner/dist-mxnet,EvanzzzZ/mxnet,vikingMei/mxnet,hotpxl/mxnet,solin319/incubator-mxnet,jermainewang/mxnet,indhub/mxnet,jennyzhang0215/incubator-mxnet,gautamkmr/incubator-mxnet,antoan2/incubator-mxnet,apaleyes/mxnet,rishita/mxnet,piiswrong/mxnet,antoan2/incubator-mxnet,ZihengJiang/mxnet,DickJC123/mxnet,crazy-cat/incubator-mxnet,madjam/mxnet,hpi-xnor/BMXNet,coder-james/mxnet,tlby/mxnet,yuruofeifei/mxnet,piiswrong/mxnet,navrasio/mxnet,lxn2/mxnet,fullfanta/mxnet,nicklhy/mxnet,ZihengJiang/mxnet,gautamkmr/incubator-mxnet,sergeykolychev/mxnet,kkk669/mxnet,dmlc/mxnet,hotpxl/mxnet,precedenceguo/mxnet,hpi-xnor/BMXNet,rahul003/mxnet,TuSimple/mxnet,arikpoz/mxnet,zhreshold/mxnet,formath/mxnet,tlby/mxnet,kkk669/mxnet,likelyzhao/mxnet,precedenceguo/mxnet,jamesliu/mxnet,gautamkmr/incubator-mxnet,LinkHS/incubator-mxnet,fullfanta/mxnet,weleen/mxnet,luoyetx/mxnet,jiajiechen/mxnet,coder-james/mxnet,ykim362/mxnet,pluskid/mxnet,hesseltuinhof/mxnet,reminisce/mxnet,nicklhy/mxnet,yuruofeifei/mxnet,LinkHS/incubator-mxnet,mbaijal/incubator-mxnet,arank/mxnet,precedenceguo/mxnet,yajiedesign/mxnet,ptrendx/mxnet,coder-james/mxnet,lxn2/mxnet,coder-james/mxnet,formath/mxnet,sxjscience/mxnet,vikingMei/mxnet,formath/mxnet,tornadomeet/mxnet,CodingCat/mxnet,mbaijal/incubator-mxnet,eric-haibin-lin/mxnet,weleen/mxnet,piiswrong/mxnet,CodingCat/mxnet,yajiedesign/mxnet,solin319/incubator-mxnet,lxn2/mxnet,pluskid/mxnet,tlby/mxnet,apache/incubator-mxnet,apache/incubator-mxnet,ShownX/incubator-mxnet,fullfanta/mxnet,TuSimple/mxnet,pluskid/mxnet,reminisce/mxnet,EvanzzzZ/mxnet,sxjscience/mxnet,smolix/incubator-mxnet,Prasad9/incubator-mxnet,tlby/mxnet,DR08/mxnet,navrasio/mxnet,stefanhenneking/mxnet,Northrend/mxnet,kkk669/mxnet,smolix/incubator-mxnet,ptrendx/mxnet,jiajiechen/mxnet,formath/mxnet,ptrendx/mxnet,solin319/incubator-mxnet,DickJC123/mxnet,hotpxl/mxnet,solin319/incubator-mxnet,madjam/mxnet,ptrendx/mxnet,ShownX/incubator-mxnet,Prasad9/incubator-mxnet,Mega-DatA-Lab/mxnet,formath/mxnet,formath/mxnet,Northrend/mxnet,apaleyes/mxnet,gautamkmr/incubator-mxnet,vikingMei/mxnet,CodingCat/mxnet,EvanzzzZ/mxnet,larroy/mxnet,ykim362/mxnet,yuruofeifei/mxnet,weleen/mxnet,Guneet-Dhillon/mxnet,tlby/mxnet,zhreshold/mxnet,formath/mxnet,solin319/incubator-mxnet,reminisce/mxnet,ZihengJiang/mxnet,jamesliu/mxnet,yajiedesign/mxnet,rishita/mxnet,pluskid/mxnet,yuruofeifei/mxnet,nicklhy/mxnet,ForkedReposBak/mxnet,larroy/mxnet,jennyzhang0215/incubator-mxnet,ForkedReposBak/mxnet,thirdwing/mxnet,pluskid/mxnet,lxn2/mxnet,tornadomeet/mxnet,CodingCat/mxnet,kevinthesun/mxnet,kevinthesun/mxnet,jamesliu/mxnet,ForkedReposBak/mxnet,xcgoner/dist-mxnet,crazy-cat/incubator-mxnet,formath/mxnet,gautamkmr/incubator-mxnet,xcgoner/dist-mxnet,sergeykolychev/mxnet,CodingCat/mxnet,apaleyes/mxnet,eric-haibin-lin/mxnet,fullfanta/mxnet,TuSimple/mxnet,indhub/mxnet,fullfanta/mxnet,DR08/mxnet,piiswrong/mxnet,szha/mxnet,yajiedesign/mxnet,Guneet-Dhillon/mxnet,sxjscience/mxnet,LinkHS/incubator-mxnet,Mega-DatA-Lab/mxnet,ZihengJiang/mxnet,fullfanta/mxnet,rishita/mxnet,dmlc/mxnet,Mega-DatA-Lab/mxnet,arank/mxnet,madjam/mxnet,ShownX/incubator-mxnet,Mega-DatA-Lab/mxnet,sxjscience/mxnet,ykim362/mxnet,DR08/mxnet,thirdwing/mxnet,Ldpe2G/mxnet,jennyzhang0215/incubator-mxnet,wangyum/mxnet,ForkedReposBak/mxnet,rahul003/mxnet,piiswrong/mxnet,ForkedReposBak/mxnet,sergeykolychev/mxnet,jermainewang/mxnet,antoan2/incubator-mxnet,ZihengJiang/mxnet,crazy-cat/incubator-mxnet,DR08/mxnet,kevinthesun/mxnet,indhub/mxnet,Mega-DatA-Lab/mxnet,larroy/mxnet,luoyetx/mxnet,yajiedesign/mxnet,xcgoner/dist-mxnet,yuruofeifei/mxnet,TuSimple/mxnet,eric-haibin-lin/mxnet,arank/mxnet,szha/mxnet,tlby/mxnet,thirdwing/mxnet,navrasio/mxnet,rahul003/mxnet,wangyum/mxnet,jennyzhang0215/incubator-mxnet,hpi-xnor/BMXNet,hpi-xnor/BMXNet,reminisce/mxnet,ShownX/incubator-mxnet,weleen/mxnet,ptrendx/mxnet,hpi-xnor/BMXNet,Guneet-Dhillon/mxnet,saurabh3949/mxnet,xcgoner/dist-mxnet,yajiedesign/mxnet,antoan2/incubator-mxnet,luoyetx/mxnet,thirdwing/mxnet,arank/mxnet,jermainewang/mxnet,likelyzhao/mxnet,rishita/mxnet,tornadomeet/mxnet,hesseltuinhof/mxnet,sergeykolychev/mxnet,larroy/mxnet,danithaca/mxnet,smolix/incubator-mxnet,jiajiechen/mxnet,vikingMei/mxnet,ptrendx/mxnet,zhreshold/mxnet,stefanhenneking/mxnet,apaleyes/mxnet,stefanhenneking/mxnet,arikpoz/mxnet,fullfanta/mxnet,madjam/mxnet,luoyetx/mxnet,saurabh3949/mxnet,precedenceguo/mxnet,Guneet-Dhillon/mxnet,saurabh3949/mxnet,Prasad9/incubator-mxnet,lxn2/mxnet,Prasad9/incubator-mxnet,vikingMei/mxnet,Ldpe2G/mxnet,likelyzhao/mxnet,larroy/mxnet,hpi-xnor/BMXNet,Ldpe2G/mxnet,tornadomeet/mxnet,xcgoner/dist-mxnet,Ldpe2G/mxnet,ptrendx/mxnet,szha/mxnet,Prasad9/incubator-mxnet,mbaijal/incubator-mxnet,xcgoner/dist-mxnet,ZihengJiang/mxnet,nicklhy/mxnet,reminisce/mxnet,szha/mxnet,navrasio/mxnet,Guneet-Dhillon/mxnet,ykim362/mxnet,danithaca/mxnet,Mega-DatA-Lab/mxnet,ShownX/incubator-mxnet,leezu/mxnet,CodingCat/mxnet,navrasio/mxnet,szha/mxnet,jennyzhang0215/incubator-mxnet,zhreshold/mxnet,yajiedesign/mxnet,vikingMei/mxnet,stefanhenneking/mxnet,danithaca/mxnet,arikpoz/mxnet,tlby/mxnet,kkk669/mxnet,ForkedReposBak/mxnet,thirdwing/mxnet,DR08/mxnet,ShownX/incubator-mxnet,crazy-cat/incubator-mxnet,Prasad9/incubator-mxnet,wangyum/mxnet,hesseltuinhof/mxnet,Mega-DatA-Lab/mxnet,crazy-cat/incubator-mxnet,jamesliu/mxnet,indhub/mxnet,crazy-cat/incubator-mxnet,arikpoz/mxnet,nicklhy/mxnet,LinkHS/incubator-mxnet,madjam/mxnet,piiswrong/mxnet,thirdwing/mxnet,DR08/mxnet,likelyzhao/mxnet,coder-james/mxnet,mbaijal/incubator-mxnet,madjam/mxnet,rishita/mxnet,hesseltuinhof/mxnet,hotpxl/mxnet,stefanhenneking/mxnet,yajiedesign/mxnet,arank/mxnet,arank/mxnet,ptrendx/mxnet,navrasio/mxnet,eric-haibin-lin/mxnet,dmlc/mxnet,navrasio/mxnet,kevinthesun/mxnet,Ldpe2G/mxnet,leezu/mxnet,reminisce/mxnet,stefanhenneking/mxnet,solin319/incubator-mxnet,eric-haibin-lin/mxnet,arikpoz/mxnet,saurabh3949/mxnet,Guneet-Dhillon/mxnet,lxn2/mxnet,wangyum/mxnet,saurabh3949/mxnet,rishita/mxnet,coder-james/mxnet,antoan2/incubator-mxnet,mbaijal/incubator-mxnet,reminisce/mxnet,hotpxl/mxnet,weleen/mxnet,TuSimple/mxnet,smolix/incubator-mxnet,smolix/incubator-mxnet,Prasad9/incubator-mxnet,smolix/incubator-mxnet,sergeykolychev/mxnet,smolix/incubator-mxnet,rahul003/mxnet,antoan2/incubator-mxnet,saurabh3949/mxnet,arank/mxnet,piiswrong/mxnet,sxjscience/mxnet,leezu/mxnet,jermainewang/mxnet,DickJC123/mxnet,solin319/incubator-mxnet,tornadomeet/mxnet,hesseltuinhof/mxnet,ptrendx/mxnet,lxn2/mxnet,xcgoner/dist-mxnet,ForkedReposBak/mxnet,reminisce/mxnet,TuSimple/mxnet,EvanzzzZ/mxnet,CodingCat/mxnet,jiajiechen/mxnet,jennyzhang0215/incubator-mxnet,leezu/mxnet,vikingMei/mxnet,likelyzhao/mxnet,piiswrong/mxnet,kkk669/mxnet,mbaijal/incubator-mxnet,LinkHS/incubator-mxnet,Northrend/mxnet,TuSimple/mxnet,stefanhenneking/mxnet,jiajiechen/mxnet,wangyum/mxnet,jennyzhang0215/incubator-mxnet,rishita/mxnet,leezu/mxnet,solin319/incubator-mxnet,tornadomeet/mxnet,yuruofeifei/mxnet,DR08/mxnet,pluskid/mxnet,dmlc/mxnet,Northrend/mxnet,arikpoz/mxnet,kkk669/mxnet,Northrend/mxnet