I would like to know how to call rerender method in component controller, its mentioned in the lightning pdf we need to call rerender explicitly if there are no updates to the component data but stilll want to rerender the component.

Hi i have a custom button on detai page.On click opens a VF page - where i have a save button.
On click of save , it inserts sme records. so after that i have to return to detail page.which i can.
But i want is the "Thank You! (n) Records inserted" some thing like this message.

When i run the test method then i got the  error "  System.DmlException: Insert failed. First exception on row 0; first error: FIELD_INTEGRITY_EXCEPTION, Chatter Answers User is not allowed for this License Type.: [UserPermissions] ""


@isTest(seeAllData=false)
private class ChatterAnswersAuthProviderRegTest {
    static testMethod void validateCreateUpdateUser() {
        User thisUser = [ select Id from User where Id = :UserInfo.getUserId() ];
        System.runAs ( thisUser ) {
            Auth.UserData userData = new Auth.UserData('testId', 'testFirst', 'testLast',
            'testFirst testLast', 'no-reply@salesforce.com', null, 'testuserlong', 'en_US', 'facebook',
            null, new Map<String, String>{'language' => 'en_US'});
            ChatterAnswersAuthProviderRegistration reg = new ChatterAnswersAuthProviderRegistration();
            Profile[] p = [SELECT Id FROM Profile WHERE Name = 'System Administrator'];
            User[] adminUser = [SELECT Id, Firstname, Lastname FROM User WHERE IsActive = true and ProfileId =: p[0].Id LIMIT 1];
            
            reg.setSiteAdminUserId(adminUser[0].Id);
            User newUser = reg.createUser(null, userData);
            System.assert(newUser != null, 'A new user should have been created');
            System.assertEquals(newUser.Firstname, 'testFirst', 'First name should have been same');
            System.assertEquals(newUser.Lastname, 'testLast', 'Last name should have been same');
            System.assertEquals(newUser.Email, 'no-reply@salesforce.com', 'Email should have been same');
            
            Profile profile = [Select Id from Profile Where Name = 'Chatter Moderator User' ];
            
            Contact c = new Contact();
            c.AccountId = (newUser.Username.split('@'))[0];
            c.LastName = 'contactLast';
            insert(c);
            
            newUser.Alias = 'firstusr';
            newUser.TimeZoneSidKey = 'America/Los_Angeles';
            newUser.LocaleSidKey = 'en_US';
            newUser.EmailEncodingKey = 'UTF-8';
            newUser.LanguageLocaleKey = 'en_US';
            newUser.ContactId = c.Id;
            newUser.ProfileId = profile.Id;
            
            //Insert User
            insert(newUser);
            
            Auth.UserData updateUserData = new Auth.UserData('testId', 'updatedFirst', 'updatedLast',
            'updatedFirst updatedLast', 'no-reply@new.salesforce.com', null, 'testuserlong', 'en_US', 'facebook',
            null, new Map<String, String>{'language' => 'en_US'});
            reg.updateUser(newUser.Id, null, updateUserData);
            
            User dbUser =  [SELECT Id, Firstname, Lastname, Email FROM User WHERE Id = :newUser.Id];
            System.assertEquals(dbUser.Firstname, 'updatedFirst', 'First name should have been updated');
            System.assertEquals(dbUser.Lastname, 'updatedLast', 'Last name should have been updated');
            System.assertEquals(dbUser.Email, 'no-reply@new.salesforce.com', 'Email should have been updated');
        }
    }
}