Bug#545763: Reproduction method

[Florent Charton]

First way :
1. Open a nautilus browser window
2. Click Edition > Preferences
3. You no more have desktop icons

Second way :
1. Run in a terminal : nautilus-file-management-properties
2. Observe the segfault

The behaviours are different, because the second method does not make 
the desktop icons disappear. A few days ago, both methods were equivalent.