D25922: Don't use a verified nullptr as a data source

[Aleix Pol Gonzalez]

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

REPOSITORY
  R235 Attica

BRANCH
  dont-use-null-qcoreapp-instance (branched from master)

REVISION DETAIL
  https://phabricator.kde.org/D25922

To: leinir, #frameworks, #knewstuff, #plasma, ronaldv, apol
Cc: kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns