message: Stop grpc server on test teardown.
diff: @@ -61,10 +61,7 @@ class RpcOpTest(test.TestCase, rpc_op_test_base.RpcOpTestBase):
  self._server = server
  def tearDown(self):
  - # TODO(ebrevdo): Figure out why this sometimes times out.
  - # self._service.ExitLoop()
  - # self._service_thread.join()
  - # self._server.stop()
  + self._server.stop(grace=None)
  super(RpcOpTest, self).tearDown()
  