Invalid argument supplied for foreach() in cors_init() line 143

When configuring CORS I was getting this error on every page load. I was able to fix it by changing this...

          foreach ($values as $value) {
            drupal_add_http_header($header, $value, TRUE);
          }

...to this...

          foreach ((array) $values as $value) {
            drupal_add_http_header($header, $value, TRUE);
          }