D6059: Close notifications that don't have a default action by clicking

[Kai Uwe Broulik]

broulik added a reviewer: VDG.

REPOSITORY
  R120 Plasma Workspace

REVISION DETAIL
  https://phabricator.kde.org/D6059

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