You'll also notice the second partition now shows as a ntfs formatted partition. It didn't do that before.
Can you post one more diagnostics so I can be sure UD is processing the disk information correctly and another copy of the unassigned.devices.ini?
This is a long standing issue and had nothing to do with any recent changes in UD that I can see. What is happening is the third partition has no udev information and because UD sees it as part of the unassigned disk, UD was trying to get information from udev. udev was returning null information and UD didn't handle it well. The error was on the data, not in a php file. That's why I was struggling to find the problem.