The kernel can now publish a property describing the layout of virtual
hardware buttons on the touchscreen. These outside of the display
area (outside of the absolute x and y controller range the driver
reports), and when the user presses on them a key event will be
generated rather than a touch event.
This also includes a number of tweaks to the absolute controller
processing to make things work better on the new screens. For
example, we now reject down events outside of the display area.
Still left to be done is the ability to cancel a key down event,
so the user can slide up from the virtual keys to the touch screen
without causing a virtual key to execute.
