Use xcb to create and manage the X11 backend of Outline. In addition the
used background pixmaps are rendered with XRender instead of using a
QPainter on a QPixmap. This is done because QPixmap is no longer bound to
an X Pixmap.
To create the XRender Picture the available functionality from
kwinxrenderutils is used. To be able to use it in KWin core the compile
option to build without XRender is removed for kwinxrenderutils, but
still supported for effects.
Obviously the port to XCB is not complete as xremderutils itself is still
on XLib.
REVIEW: 108642