Impacted versions: 10.0

Steps to reproduce:
- define a rule with `Appears on Payslip` unticked and with account defined
- define a contract for an employee, and linked to a structure which has the modified rule

Current behavior: the rule is not computed and move is not written to journal.

Expected behavior: account move related to hidden rule should be present in salary journal

Video/Screenshot link (optional):

_inherit = 'hr.employee'
    _description = 'Employee'
    slip_ids = fields.One2many('hr.payslip', 'employee_id', string='Payslips', readonly=True)
    payslip_count = fields.Integer(compute='_compute_payslip_count', string='Payslips', groups="hr_payroll.group_hr_payroll_user")
    @api.multi
    def _compute_payslip_count(self):
        for employee in self:
            employee.payslip_count = len(employee.slip_ids)