A drawin's and a client's bounding and clip shape can now be queried and is
returned as a cairo surface. Also, a client window's shape (e.g. xeyes setting
its own shape) can be queried via c.shape_client_bounding and
c.shape_client_clip. All of these properties now emit signals when changed.
(This also silently fixes a bug in luaA_drawin_set_shape_bounding() which forgot
to include the drawin's border in its size calculation)
Signed-off-by: Uli Schlachter <psychon@znc.in>
56c5797905