D13848: Fix device label with unknown size

[David Edmundson]

davidedmundson accepted this revision.
This revision is now accepted and ready to land.

REPOSITORY
  R245 Solid

REVISION DETAIL
  https://phabricator.kde.org/D13848

To: broulik, davidedmundson
Cc: bruns, kde-frameworks-devel, michaelh, ngraham