The OSD's icon is based on the implicitSize of the IconItem.
For most icons this will be a hardcoded value from
KIconLoader::global()->currentSize
However, since bc33f0470d4d6bcbf30475f85b36705e8a99528b in
plasma-framework we sometimes return that value, sometimes will return the
source size of the underlying image depending on internal paths of how
the icon is loaded and whether it was in the plasma theme or not.
This patch overrides the implicitWidth given to the layout to be the
standard icon size.
BUG: 400083