D6141: make shadows work for windows 100%width or height

[Marco Martin]

mart abandoned this revision.

REPOSITORY
  R108 KWin

REVISION DETAIL
  https://phabricator.kde.org/D6141

To: mart, #plasma, #kwin, graesslin
Cc: luebking, mvourlakos, davidedmundson, plasma-devel, kwin, ZrenBot, spstarr, 
progwolff, lesliezhai, ali-mohamed, hardening, jensreuterberg, abetts, sebas, 
apol, mart, lukas