Allow cogl_wayland_onscreen_get_surface to be used non-foreignly
Allow cogl_wayland_onscreen_get_surface to be used non-foreignly

cogl_wayland_onscreen_get_surface previously only worked if the
onscreen had a foreign surface on it. However there is no reason why
this shouldn't also work fine for manipulating the surface that Cogl
created as well. We may want to consider adding a separate getter for
the foreign surface that can be used before the framebuffer is
allocated.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 6bc12947a51224b70525893143bfe421723ce255)

Distrotech/cogl,Distrotech/cogl,Distrotech/cogl,Distrotech/cogl