/**
  * Construct a sanitiser from a given HtmlEditorConfig
  *
  * Note that we build data structures from the current state of HtmlEditorConfig - later changes to
  * the passed instance won't cause this instance to update it's whitelist
  *
  * @param HtmlEditorConfig $config
  */
 public function __construct(HtmlEditorConfig $config)
 {
     $valid = $config->getOption('valid_elements');
     if ($valid) {
         $this->addValidElements($valid);
     }
     $valid = $config->getOption('extended_valid_elements');
     if ($valid) {
         $this->addValidElements($valid);
     }
 }