[patch] Null file path fails to generate filename
|Reported by:||Owned by:||Adrian Holovaty|
|Has patch:||yes||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
If you have a file field that is null, calling get_FIELD_filename will result in an exception from os.path.join.
I created a simliar solution already implemented in get_FIELD_url to avoid this problem.