Method finaliseUninstall

/**
 * Method to finalise the uninstallation processing
 *
 * @return  boolean
 *
 * @since   4.0.0
 * @throws  \RuntimeException
 */
protected function finaliseUninstall() : bool
{
    $db = $this->parent->getDbo();
    // Remove the schema version
    $query = $db->getQuery(true)->delete($db->quoteName('#__schemas'))->where($db->quoteName('extension_id') . ' = :extension_id')->bind(':extension_id', $this->extension->extension_id, ParameterType::INTEGER);
    $db->setQuery($query);
    $db->execute();
    // Clobber any possible pending updates
    $update = Table::getInstance('update');
    $uid = $update->find(['element' => $this->extension->element, 'type' => $this->type]);
    if ($uid) {
        $update->delete($uid);
    }
    File::delete(JPATH_MANIFESTS . '/packages/' . $this->extension->element . '.xml');
    $folder = $this->parent->getPath('extension_root');
    if (Folder::exists($folder)) {
        Folder::delete($folder);
    }
    $this->extension->delete();
    return true;
}