fix typo (xp => xc) and trivial revise of test names
fix typo (xp => xc) and trivial revise of test names

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