[FIX] web: Reset correctly the selection on reference fields

Purpose
=======

If the model on a reference fields is not modified from the interface
by the user but by the server, the selection is not correctly
recomputed on the interface.

Specification
=============

By calling super first on the '_reset' method, the new model
is taken into account when resetting the selection.

addons/web/static/src/js/fields/relational_fields.js

@@ -2499,9 +2499,9 @@ var FieldReference = FieldMany2One.extend({
      * @private
      */
     _reset: function () {
+        this._super.apply(this, arguments);
         var value = this.$('select').val();
         this._setState();
-        this._super.apply(this, arguments);
         this.$('select').val(this.value && this.value.model || value);
     },
     /**