framework/web/Session.php
public function init()
    {
        parent::init();
        register_shutdown_function([$this, 'close']);
        if ($this->getIsActive()) {
            Yii::warning('Session is already started', __METHOD__);
            $this->updateFlashCounters();
        }
    }
public function init()
    {
        parent::init();
        register_shutdown_function([$this, 'close']);
        if ($this->getIsActive()) {
            Yii::warning('Session is already started', __METHOD__);
            $this->updateFlashCounters();
        }
    }
Initializes the application component.
This method is required by IApplicationComponent and is invoked by application.