frameworks: fix kwrite session management
Review Request #114607 - Created Dec. 22, 2013 and submitted
To my best knowledge, this should fix the compiler virtual override warnings and keep/fix kwrite session working. Don't use session manager by myself and xsm doesn't seems to be working properly, so I'm not sure if it realy works or not. I was looking at the implementation in kxmlgui and QSessionManager and it seems the tests (quite ugly one) could be written for this, though.