Piwik\Plugins\CustomVariables\Menu::configureAdminMenu PHP Method

    public function configureAdminMenu(MenuAdmin $menu)
    {
        $userPreferences = new UserPreferences();
        $default = $userPreferences->getDefaultWebsiteId();
        $idSite = Common::getRequestVar('idSite', $default, 'int');
        if (Piwik::isUserHasAdminAccess($idSite)) {
            $menu->addDiagnosticItem('Custom Variables', $this->urlForAction('manage'), $orderId = 20);
        }
    }