Add an own input and focus implementation

Do not use the shared wayland-server input and focus implementation any
longer. It just makes the code complicate and ugly using C-style APIs
without much benefit and it is much nicer to implement them ourselves
with a Qt API. The shared input and focus code got removed from Wayland
1.2 because of that.

Change-Id: Iab7181e743e7fa26004b0dd93a827dc8f86ca676
Reviewed-by: Andy Nichols <andy.nichols@digia.com>
No need for Surface to be a ::wl_surface anymore

This struct was only required by the wayland-server input/focus code
which we do not use anymore.

Change-Id: I6a70511bc731ea43f7e92b0196f0e5938148a814
Reviewed-by: Andy Nichols <andy.nichols@digia.com>
Fix SurfaceBuffer to support Wayland 1.2

The new wl_shm_buffer in Wayland 1.2 is no wl_buffer anymore, so use
wl_resource instead of wl_buffer.

Change-Id: Ie208c6b78f88eb942d88a58c6fa8944fc2864fb7
Reviewed-by: Andy Nichols <andy.nichols@digia.com>