D26532: Don't use KWindowSystem on Android

[Aleix Pol Gonzalez]

apol accepted this revision.

REPOSITORY
  R289 KNotifications

BRANCH
  nokwindowsystem

REVISION DETAIL
  https://phabricator.kde.org/D26532

To: nicolasfella, #frameworks, vkrause, apol
Cc: dfaure, kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns