If that is still the crash handler that I wrote about 5-6 years ago (and which was by default disabled) then it is likely that this call was added because something didn't work otherwise (I sure didn't know about that function, so if it's there, it probably came from a patch to fix an issue).
If that's a different implementation written by someone else, forget the last paragraph.
About saving files from the crash handler, please don't do that. You don't know what you're saving when the application is crashing. This is asking for trouble (also, the goal should be not to have any crashes, not to make crashes feature-rich).