Session does not save used Kit

When you are switching between the Sessions the used Kit from the old Session is used, instead of the Kit that the Session used the last time.

-> Steps to reproduce.

 1.) Open a new Session and open an example Project, use Default Kit for the Project
       for example GCC 64Bit

 2.) Open a new Session and open the same Project but this time select a different Kit for the
       Project, for example Android

3.) Open the first Session again, the saved Kit is now Android instead of GCC 64Bit.