The extension handling is removed from kwinglobals and moved into the
xcbutils in KWin core in namespace KWin::Xcb. The motivation for this
change is that the Extensions are only used in KWin core and are marked
as internal. So there is no need to have them in the library.
What remains in Extensions are the non-native pixmaps. This will be
removed once we are on Qt 5 as QPixmap can no longer reference an XPixmap.
The remaining code in kwinglobals also still initialize the XLib versions
of extensions emitting events. It seems like there are no XEvents emitted
if not done so even if the extension is correctly initialized with xcb.
This needs to be removed once the event handling is ported over to xcb.
REVIEW: 107832
b967527db3