<button string="Confirm" name="confirm" states="draft" type="workflow" icon="gtk-yes" groups="base.group_hr_user,base.group_hr_manager"/>
<button string="Approve" name="validate" states="confirm" type="workflow" icon="gtk-apply" groups="base.group_hr_manager"/>
<button string="Approved" name="second_validate" states="validate1" type="workflow" icon="gtk-apply" groups="base.group_hr_manager"/>
<button string="Confirm" name="confirm" states="draft" type="workflow" icon="gtk-yes" groups="base.group_hr_user,base.group_hr_manager"/>
<button string="Approve" name="validate" states="confirm" type="workflow" icon="gtk-apply" groups="base.group_hr_manager"/>
<button string="Approved" name="second_validate" states="validate1" type="workflow" icon="gtk-apply" groups="base.group_hr_manager"/>