D26757: Reduce dependencies on Windows

[Hannah von Reth]

vonreth added reviewers: broulik, brute4s99, vkrause.

REPOSITORY
  R289 KNotifications

REVISION DETAIL
  https://phabricator.kde.org/D26757

To: vonreth, broulik, brute4s99, vkrause
Cc: kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns