context_test.cc: remove using CheckThreadSafety
context_test.cc: remove using CheckThreadSafety

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