nsISessionStore keeps track of the current browsing state - i.e.
 tab history, cookies, scroll state, form data, POSTDATA and window features
 - and allows to restore everything into one window.
[scriptable, uuid(c0b185e7-0d21-46ac-8eee-7b5065ee7ecd)]
interface nsISessionStartup : nsISupports


 What type of session we're restoring. If we have a session, we're
 either restoring state from a crash or restoring state that the user
 requested we save on shutdown.
const unsigned long NO_SESSION = 0

const unsigned long RECOVER_SESSION = 1

const unsigned long RESUME_SESSION = 2


readonly attribute unsigned long sessionType

readonly attribute AString state


 Determine if session should be restored 
boolean doRestore()