Add tests for backward order check
Add tests for backward order check

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