KWin opengl tests (e.g. sceneOpenGL) need DRI devices to actually run the test. Currently we cannot run them because 14.04 has a fairly old kernel.
Once we migrate to 16.04 we should do one of the following:
Device forward
This only makes sense if /dev/dri/* contains a card node, control node and render node.
approximately do docker --device /dev/dri/* to selectively forward all DRI nodes (possibly only for kwin test) into docker.
vgem
Virtual DRI nonense. Load vgem kernel module if native /dev/dri/ on host doesn't have the relevant nodes and we need virtual ones. Possibly still needs --device forwarding into docker.