Fix the check on LabeledImageDataset format
Fix the check on LabeledImageDataset format

okuta/chainer,okuta/chainer,jnishi/chainer,jnishi/chainer,cupy/cupy,aonotas/chainer,keisuke-umezawa/chainer,ktnyt/chainer,kikusu/chainer,hvy/chainer,ktnyt/chainer,kashif/chainer,keisuke-umezawa/chainer,kikusu/chainer,hvy/chainer,jnishi/chainer,wkentaro/chainer,jnishi/chainer,okuta/chainer,cupy/cupy,ktnyt/chainer,ronekko/chainer,delta2323/chainer,chainer/chainer,pfnet/chainer,wkentaro/chainer,niboshi/chainer,wkentaro/chainer,chainer/chainer,ktnyt/chainer,chainer/chainer,ysekky/chainer,cupy/cupy,okuta/chainer,hvy/chainer,rezoo/chainer,niboshi/chainer,keisuke-umezawa/chainer,hvy/chainer,cupy/cupy,niboshi/chainer,chainer/chainer,niboshi/chainer,keisuke-umezawa/chainer,kiyukuta/chainer,tkerola/chainer,wkentaro/chainer,anaruse/chainer