This prepares the headers for exporting symbols using visibility
attributes or __declspec(dllexport), so that we do not need to maintain
symbols listing files, as this is what was and is done in GLib and GTK+.
Also remove shaper_options argument to hb_shape_full(). That was
unused and for "future". Let it go.
More shaper API coming in preparation for plan/planned API.
Users should #include <hb.h> (or hb-ft.h, hb-glib.h, etc), but
never things like hb-shape.h directly. This makes it easier to
refactor headers later on without breaking compatibility.
Chun-wei Fan
Behdad Esfahbod