Saving any setting in "Super Admin > Blogs > Edit" breaks activity as frontpage

[r-a-y]

I have the activity stream set as frontpage.

Now, I add a new user via "Super Admin > Blogs > Edit".
Frontpage is reset to post index.

Problem can be remedied by resaving the activity stream as frontpage in "Settings > Reading".

[DJPaul]

Closing this as this front page handling needs to be written for trunk; see #2743