Anonymous users do not see quiz question validation.

Problem/Motivation

When an anonymous user is taking a quiz they never see any status messages telling them about quiz question validation problems. This is because the user is redirected via drupal_goto() before the drupal_set_message() call that sends the validation message to the session.

Proposed resolution

Essentially, a call to drupal_set_message() should also be placed before the call to drupal_goto(), which stops code execution.

Remaining tasks

I think the patch attached is pretty simple. If everything checks out with the module maintainers then please apply it :)

User interface changes

Just that anonymous users now receive indication as to why they can't progress through the quiz if the question they are on fails to validate.

API changes

Line 1993 of quiz.module is changed here.
Code before:

      // Avoid caching for anonymous users
      if (!$user->uid) {
        drupal_goto('node/' . $quiz->nid . '/take', array('query' => array('quizkey' => md5(mt_rand() . REQUEST_TIME))));
      }

Code after

      // Avoid caching for anonymous users
      if (!$user->uid) {
        drupal_set_message($q_passed_validation, 'error');        
        drupal_goto('node/' . $quiz->nid . '/take', array('query' => array('quizkey' => md5(mt_rand() . REQUEST_TIME))));
      }