User:report does not show the correct amount if s3 is primary storage

[AlexAndBear]

Steps to reproduce

1. Create an ownCloud 10.8 instance with s3 as primary storage
2. Login and upload some files
3. Run occ user:report

Expected behaviour

User directory count should be 1

Actual behaviour

User directory count should is 0

[AlexAndBear]

FYI @phil-davis @jvillafanez @JammingBen