gtk_icon_theme_load_icon_async is not thread safe
I was prototyping something about Nautilus and realized that we use the non-async function of gtk_icon_info_load_icon. So I though about using the async version, gtk_icon_info_load_icon_async although it seemed odd to me because gtk+ is not thread safe.
Well yeah, I got all kind of weird behavior and crashes when switched to the async version. gtk_icon_info_load_icon might return an internal pixbuf, which could be being accessed or destroyed in some other thread.
So I wonder if that should be either removed or make sure the threaded operation just executes the thread safe parts (the scaling and render should be fine, the problem is the icon info itself and accessing the internal pixbuf in it).
In some quick testing, some code paths of that call got around 0.004 seconds in my system, which is significant.