D5146: Implement UI feedback for long-running searches, and no-results

[Dan Leinir Turthra Jensen]

leinir edited the summary of this revision.

REPOSITORY
  R134 Discover Software Store

REVISION DETAIL
  https://phabricator.kde.org/D5146

To: leinir, apol, #vdg
Cc: mart, plasma-devel, progwolff, lesliezhai, ali-mohamed, jensreuterberg, 
abetts, sebas, apol