D6246: Don't rely on QQuickWindow delivering QEvent::Ungrab as mouseUngrabEvent (as it no longer does in Qt 5.8+)

[David Edmundson]

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

REPOSITORY
  R296 KDeclarative

BRANCH
  master

REVISION DETAIL
  https://phabricator.kde.org/D6246

To: hein, #plasma, davidedmundson
Cc: plasma-devel, #frameworks, ZrenBot, spstarr, progwolff, lesliezhai, 
ali-mohamed, jensreuterberg, abetts, sebas, apol, mart, lukas