Handset cohabitation: Ubuntu for Android

Well you have only one graphics driver, and it's on Android's side, so that implies SurfaceFlinger is the ultimate compositor and Ubuntu is just one object (albeit using the full second screen), correct? Having the Android app display on top of the Ubuntu desktop is then just a compositing issue: "blit that window on top of that framebuffer at that position".

Please let me know if I'm talking BS :-)