gdk: Use the correct surface size when creating surfaces
gdk: Use the correct surface size when creating surfaces

Previously we used the size of the csw window, which could easily be
huge and cause CAIRO_SURFACE_INVALID_SIZE errors. If we use the real
size, we work around this problem. The surface can now potentially be
bigger than before but we should handle that when clipping in csw.

https://bugzilla.gnome.org/show_bug.cgi?id=633701

Unity-Technologies/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk,Unity-Technologies/gtk,johne53/MB3Gtk-2,johne53/MB3Gtk-2,Distrotech/gtk,Unity-Technologies/gtk,Distrotech/gtk,Distrotech/gtk,Unity-Technologies/gtk,johne53/MB3Gtk-2,Distrotech/gtk,Distrotech/gtk,johne53/MB3Gtk-2