Fix the unittest for KernelRegistry
Fix the unittest for KernelRegistry

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