Remove unnecessary loop for popping
Remove unnecessary loop for popping

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