This feels a lot more consistent and Unixy:
create_shared_buffer() => shbuf_create()
share_buffer_with() => shbuf_allow_pid()
share_buffer_globally() => shbuf_allow_all()
get_shared_buffer() => shbuf_get()
release_shared_buffer() => shbuf_release()
seal_shared_buffer() => shbuf_seal()
get_shared_buffer_size() => shbuf_get_size()
Also, "shared_buffer_id" is shortened to "shbuf_id" all around.
This allows windows/widgets to learn when something is being dragged
over them. They can then repaint themselves somehow to indicate that
they are willing to accept a drop.
Currently this is piggybacking somewhat on the mouse event mechanism
in WindowServer. I'm not sure that's the best design but it seemed
easier to do it this way right now.
