protected function getAbTesting()
 {
     if (empty($this->abTesting)) {
         $this->abTesting = AbTesting::getInstance();
     }
     return $this->abTesting;
 }
<?php

/** @var $abTesting AbTesting */
$abTesting = AbTesting::getInstance();
$yes = wfMsg('abtesting-flag-set-short');
?>
<tr class="exp<?php 
echo empty($showDetails) ? ' collapsed' : '';
?>
" data-id="<?php 
echo $experiment['id'];
?>
">
    <td class="arrow-nav"><img class="arrow" src="<?php 
echo $wg->BlankImgUrl;
?>
" /></td>
    <td><?php 
echo $experiment['id'];
?>
</td>
    <td class="<?php 
echo $experiment['css_class'];
?>
"><?php 
echo htmlspecialchars($experiment['name']);
?>
</td>
    <td><?php 
echo htmlspecialchars($experiment['description']);
?>