D9114: [Breeze window decoration] Don't repaint title bar if not damaged

[Martin Flöser]

graesslin accepted this revision.

REPOSITORY
  R31 Breeze

REVISION DETAIL
  https://phabricator.kde.org/D9114

To: broulik, #plasma, hpereiradacosta, graesslin, davidedmundson
Cc: plasma-devel, ZrenBot, progwolff, lesliezhai, ali-mohamed, jensreuterberg, 
abetts, sebas, apol, mart