Large directories were not being added to data projects with all their contents

This is a very nasty bug. If you have a large directory and you add it into a data project, the directory gets added, but possibly not its full contents.

I encountered this trying to backup family photos, but the project size wasn't adding up. Then I noticed that one of the directories, which should contain 488 files and 3 subdirs, only had 91 files within the data project.