[IMP] Improve test case "editable list: value reset by an onchange",

as we do not set value on datetime field on first click so we need to
set value in datetime picker explicitly to trigger onchange

addons/web/static/tests/fields/relational_fields_tests.js

@@ -8,6 +8,7 @@ var ListView = require('web.ListView');
 var relationalFields = require('web.relational_fields');
 var testUtils = require('web.test_utils');
 var Widget = require('web.Widget');
+var fieldUtils = require('web.field_utils');
 
 var createView = testUtils.createView;
 
@@ -4781,6 +4782,8 @@ QUnit.module('relational_fields', {
         form.$('.o_data_row .o_field_widget').val('a name').trigger('input');
         def = $.Deferred();
         form.$('.o_datepicker_input').click(); // focusout o2m and set value to today
+        var dateTimeVal = fieldUtils.format.datetime(moment(), {timezone: false});
+        form.$('.o_datepicker_input').val(dateTimeVal).trigger('change');
 
         // resolve the onchange def
         def.resolve();