Attribute 'class' value passed to l() function should be an array

Hi all,

One of our modules uses CSS classes assigned to links and buttons to add custom logic. From this module we receive multiple warnings that:

Warning: in_array() expects parameter 2 to be array, string given in func()...

According to Drupal 7.x documentation attribute 'class' should be an array: https://api.drupal.org/api/drupal/developer%21topics%21forms_api_referen...
One of the places where we identified the problem is line where implode function is executed:

'class' => implode(' ', $menu_classes),

which can be changed to simply:

'class' => $menu_classes,