Fix BatchNormalization.check_type_backward
Fix BatchNormalization.check_type_backward

jnishi/chainer,wkentaro/chainer,bayerj/chainer,wkentaro/chainer,chainer/chainer,woodshop/chainer,keisuke-umezawa/chainer,ktnyt/chainer,ronekko/chainer,minhpqn/chainer,ytoyama/yans_chainer_hackathon,wkentaro/chainer,AlpacaDB/chainer,cemoody/chainer,chainer/chainer,sou81821/chainer,chainer/chainer,woodshop/complex-chainer,jnishi/chainer,t-abe/chainer,AlpacaDB/chainer,okuta/chainer,okuta/chainer,anaruse/chainer,rezoo/chainer,muupan/chainer,kiyukuta/chainer,laysakura/chainer,1986ks/chainer,hvy/chainer,hvy/chainer,Kaisuke5/chainer,jnishi/chainer,okuta/chainer,ktnyt/chainer,umitanuki/chainer,ikasumi/chainer,jfsantos/chainer,okuta/chainer,niboshi/chainer,muupan/chainer,ysekky/chainer,sinhrks/chainer,kuwa32/chainer,niboshi/chainer,hvy/chainer,truongdq/chainer,jnishi/chainer,benob/chainer,wavelets/chainer,kikusu/chainer,kashif/chainer,keisuke-umezawa/chainer,tigerneil/chainer,masia02/chainer,ktnyt/chainer,wkentaro/chainer,cupy/cupy,pfnet/chainer,cupy/cupy,tscohen/chainer,chainer/chainer,ktnyt/chainer,keisuke-umezawa/chainer,cupy/cupy,tkerola/chainer,delta2323/chainer,benob/chainer,niboshi/chainer,keisuke-umezawa/chainer,hvy/chainer,kikusu/chainer,niboshi/chainer,truongdq/chainer,elviswf/chainer,hidenori-t/chainer,aonotas/chainer,yanweifu/chainer,t-abe/chainer,cupy/cupy,sinhrks/chainer