[Icon Item] Round size we want to load a pixmap in

QML sizes can be fractional. In case we're asked to load a 31.5 px pixmap it would truncate
it to 31 and then round down to 22 causing a blurry result. Instead, round the size.

Differential Revision: https://phabricator.kde.org/D4040

src/declarativeimports/core/iconitem.cpp

@@ -452,7 +452,7 @@ void IconItem::loadPixmap()
         return;
     }
 
-    const int size = Units::roundToIconSize(qMin(width(), height()));
+    const int size = Units::roundToIconSize(qMin(qRound(width()), qRound(height())));
 
     //final pixmap to paint
     QPixmap result;