Together with these two sizes it is possible to provide both average sized borders (e.g., 4, 8 or 12 pixels) and wide borders (e.g., 18, 27, 40 pixels) without gaps in between.
svn path=/trunk/kdebase/kwin/; revision=253347
Since Qt propagates mouse events up the widget hierarchy, it's better
to filter out Qt events rather than X events for the decoration.
svn path=/trunk/kdebase/kwin/; revision=252346