Add non-zero device test for backend.from_chainerx
Add non-zero device test for backend.from_chainerx

pfnet/chainer,keisuke-umezawa/chainer,okuta/chainer,ktnyt/chainer,okuta/chainer,hvy/chainer,ktnyt/chainer,niboshi/chainer,jnishi/chainer,jnishi/chainer,hvy/chainer,okuta/chainer,jnishi/chainer,jnishi/chainer,tkerola/chainer,hvy/chainer,hvy/chainer,okuta/chainer,wkentaro/chainer,ktnyt/chainer,niboshi/chainer,niboshi/chainer,wkentaro/chainer,chainer/chainer,wkentaro/chainer,chainer/chainer,keisuke-umezawa/chainer,chainer/chainer,niboshi/chainer,keisuke-umezawa/chainer,chainer/chainer,wkentaro/chainer,keisuke-umezawa/chainer,ktnyt/chainer