Fix following review
Fix following review

okuta/chainer,wkentaro/chainer,hvy/chainer,hvy/chainer,niboshi/chainer,okuta/chainer,pfnet/chainer,chainer/chainer,niboshi/chainer,wkentaro/chainer,wkentaro/chainer,okuta/chainer,hvy/chainer,niboshi/chainer,okuta/chainer,hvy/chainer,chainer/chainer,niboshi/chainer,chainer/chainer,chainer/chainer,wkentaro/chainer