You can not give filter in tree view of object, instead of you can give in action of the object
in action you can give like this:
<record model="ir.actions.act_window" id="action_employee">
<field name="name">Employees</field>
<field name="res_model">Employees.Employees</field>
<field name="view_mode">tree,form</field>
<field name="domain">[('user_id','=',uid)]</field>
</record>
Hope this help