Fix critical warning in Game.timeout_cb

https://bugzilla.gnome.org/show_bug.cgi?id=724389
Revert "Revert "Ensure game is unpaused after Restart Game""

This reverts commit e357d918c587e0856d30648b95a70f75e685085c.

https://bugzilla.gnome.org/show_bug.cgi?id=724961