'Error case: _start_horcmgr() returns an error(MSGID0320-W).'

@mock.patch.object(vsp_utils, 'execute', side_effect=_execute)
@mock.patch.object(vsp_horcm, '_run_horcmstart', side_effect=_fake_run_horcmstart2)
def test_manage_existing_get_size_failed_to_start_horcmgr(self, _run_horcmstart, execute):

    global run_horcmstart_returns_error2
    run_horcmstart_returns_error2 = True
    self.assertRaises(exception.ManageExistingInvalidReference, self.driver.manage_existing_get_size, TEST_VOLUME[0], self.test_existing_failed_to_start_horcmgr)
    run_horcmstart_returns_error2 = False
