I think that the test case is just particularly harsh in showing up race conditions in window startup. I ran the test case with "sleep 1" added between the calls to eog, and did not see a single instance of this gdk_x11_window_get_xid() crash. Previously that would have been enough to trigger it. So, I would suggest that this particular bug has probably been fixed and the others are independent bugs in eog - it's possible that the test case is particularly aggressive and a normal user would never see them.
I think that the test case is just particularly harsh in showing up race conditions in window startup. I ran the test case with "sleep 1" added between the calls to eog, and did not see a single instance of this gdk_x11_ window_ get_xid( ) crash. Previously that would have been enough to trigger it. So, I would suggest that this particular bug has probably been fixed and the others are independent bugs in eog - it's possible that the test case is particularly aggressive and a normal user would never see them.