in the last commet on line 183 there is some typo

[hmos11]

//this is the correct one
$model = $this->owner;
if (!$model->isNewRecord) {
foreach ($this->fileNameAttributes as $value) {
Yii::info(var_export($this->_files, true));
if($model->{$value.'_delete'}==1 && !is_null($this->_files[$value]) ){
$oldFilePath = Yii::getAlias(str_replace('@web', '@webroot', $this->_oldUrls[$value]));
if(is_file($oldFilePath))unlink($oldFilePath);
}elseif (empty($model->{$value}) && !empty($this->_oldUrls[$value]) && $this->skipOnEmpty[$value]) {
$model->{$value} = $this->_oldUrls[$value];
}
}
}