Index: lib/accesslib.php
===================================================================
--- lib/accesslib.php	(revision 301)
+++ lib/accesslib.php	(working copy)
@@ -4387,7 +4387,7 @@
  */
 function get_users_by_capability($context, $capability, $fields='', $sort='',
         $limitfrom='', $limitnum='', $groups='', $exceptions='', $doanything=true,
-        $view=false, $useviewallgroups=false) {
+        $view=false, $useviewallgroups=false, $viewhidden=false) {
     global $CFG;
 
     $ctxids = substr($context->path, 1); // kill leading slash
@@ -4520,7 +4520,7 @@
     }
 
     /// Set up hidden role-assignments sql
-    if ($view && !has_capability('moodle/role:viewhiddenassigns', $context)) {
+    if (($view && !has_capability('moodle/role:viewhiddenassigns', $context)) || !$viewhidden) {
         $condhiddenra = 'AND ra.hidden = 0 ';
         $sscondhiddenra = 'AND ssra.hidden = 0 ';
     } else {