add tooltip content as aria label, fixes #1916

Closes #1916

Merge request studip/studip!1267

resources/assets/javascripts/bootstrap/tooltip.js

@@ -37,6 +37,7 @@ $(document).on('mouseenter mouseleave focusin focusout', '[data-tooltip],.toolti
         }
         $(this).attr('title', '');
         $(this).attr('data-tooltip', content);
+        $(this).attr('aria-label', content);
 
         tooltip = new STUDIP.Tooltip(x, y, content);
 

resources/assets/javascripts/lib/tooltip.js

@@ -87,6 +87,7 @@ class Tooltip {
      *
      * @param {int} x - Horizontal offset
      * @param {int} y - Vertical offset
+     * @param {bool} left_arrow - Vertical offset
      */
     translateArrows(x, y, left_arrow = false) {
         CSS.removeRule(`#${this.id}::before`);

templates/shared/tooltip.php

+<?php
+/**
+ * @var bool $html
+ * @var bool $important
+ * @var string $text
+ */
+?>
 <span class="tooltip tooltip-icon <? if ($important) echo 'tooltip-important'; ?>" data-tooltip <? if (!$html) printf('title="%s"', htmlReady($text)) ?> tabindex="0">
 <? if ($html): ?>
     <span class="tooltip-content"><?= $text ?></span>