fix for MDL-7474, provide alt text for ascending/descending icons in glossary

lang/en_utf8/moodle.php

@@ -112,6 +112,7 @@ $string['answer'] = 'Answer';
 $string['approve'] = 'Approve';
 $string['areyousuretorestorethis'] = 'Do you want to continue?';
 $string['areyousuretorestorethisinfo'] = 'Later in this process you will have a choice of adding this backup to an existing course or creating a completely new course.';
+$string['asc'] = 'Ascending';
 $string['assessment'] = 'Assessment';
 $string['assignadmins'] = 'Assign admins';
 $string['assigncreators'] = 'Assign creators';
@@ -357,6 +358,7 @@ $string['deletingcourse'] = 'Deleting $a';
 $string['deletingexistingcoursedata'] = 'Deleting existing course data';
 $string['deletingolddata'] = 'Deleting old data';
 $string['department'] = 'Department';
+$string['desc'] = 'Descending';
 $string['description'] = 'Description';
 $string['deselectall'] = 'Deselect all';
 $string['detailedless'] = 'Less detailed';

mod/glossary/lib.php

@@ -1482,7 +1482,7 @@ global $CFG;
              $neworder = '&sortorder=asc';
              $newordertitle = $asc;
          }
-         $icon = " <img src=\"$sortorder.gif\" border=\"0\" width=\"16\" height=\"16\" alt=\"\" />";
+         $icon = " <img src=\"$sortorder.gif\" border=\"0\" width=\"16\" height=\"16\" alt=\"". get_string($sortorder)."\" />";
      } else {
          if ( $sortkey != 'CREATION' and $sortkey != 'UPDATE' and
                $sortkey != 'FIRSTNAME' and $sortkey != 'LASTNAME' ) {