gimp_image_set_simulation_intent() attachs a "image-simulation-intent"
parasite which means that it first detaches and frees the one which was
deserialized from the XCF. When calling gimp_parasite_get_name() on this
later on, we were working on a dangling pointer. It means that the fact
we didn't have crashes most of the time was the unexpected part, not the
crash itself!
Same for gimp_image_set_simulation_bpc() and "image-simulation-bpc"
parasite.
The fix is to swap the order of statements to first detach the parasite.
95d580aa3a