Migration::displayMessage PHP Method

    function displayMessage($msg)
    {
        $now = time();
        $tps = Html::timestampToString($now - $this->deb);
        echo "<script type='text/javascript'>document.getElementById('" . $this->current_message_area_id . "').innerHTML=\"<p class='center'>" . addslashes($msg) . " ({$tps})</p>\";" . "</script>\n";
        $this->flushLogDisplayMessage();
        $this->lastMessage = array('time' => time(), 'msg' => $msg);
        Html::glpi_flush();
    }

 public static function install(Migration $migration)
 {
     global $DB;
     $table = getTableForItemType(__CLASS__);
     if (!TableExists($table) && !TableExists("glpi_dropdown_plugin_order_taxes")) {
         $migration->displayMessage("Installing {$table}");
         //Install
         $query = "CREATE TABLE `glpi_plugin_order_ordertaxes` (\n                  `id` int(11) NOT NULL auto_increment,\n                  `name` varchar(255) collate utf8_unicode_ci default NULL,\n                  `comment` text collate utf8_unicode_ci,\n                  PRIMARY KEY  (`id`),\n                  KEY `name` (`name`)\n               ) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;";
         $DB->query($query) or die($DB->error());
         $taxes = new self();
         foreach (array('20', '5.5', '19.6') as $tax) {
             $taxes->add(array('name' => $tax));
         }
     } else {
         //Update
         $migration->displayMessage("Migrating {$table}");
         //1.2.0
         $migration->renameTable("glpi_dropdown_plugin_order_taxes", $table);
         $migration->changeField($table, "ID", "id", "int(11) NOT NULL auto_increment");
         $migration->changeField($table, "name", "name", "varchar(255) collate utf8_unicode_ci default NULL");
         $migration->changeField($table, "comments", "comment", "text collate utf8_unicode_ci");
         $migration->migrationOneTable($table);
         //Remplace , by . in taxes
         foreach ($DB->request("SELECT `name` FROM `{$table}`") as $data) {
             if (strpos($data["name"], ',')) {
                 $name = str_replace(',', '.', $data["name"]);
                 $query = "UPDATE `{$table}`\n                         SET `name` = '" . $name . "'\n                         WHERE `name`= '" . $data["name"] . "'";
                 $DB->query($query) or die($DB->error());
             }
         }
     }
 }