Piwik\Plugins\Installation\Installation::dispatch PHP Method

    public function dispatch($exception = null)
    {
        if ($exception) {
            $message = $exception->getMessage();
        } else {
            $message = '';
        }
        $action = Common::getRequestVar('action', 'welcome', 'string');
        if ($this->isAllowedAction($action)) {
            echo FrontController::getInstance()->dispatch('Installation', $action, array($message));
        } else {
            Piwik::exitWithErrorMessage($this->getMessageToInviteUserToInstallPiwik($message));
        }
        exit;
    }