[gtkada] Cairo : Binding hints for cairo_image_surface_create_from_png_stream

[David SAUVAGE - AdaLabs Ltd]

Hello Nicolas,

thanks for your answer

> you mean cairo_write_func_t?
No I meant cairo_read_func_t [1].
It is cairo_surface_write_to_png_stream that uses cairo_write_func_t,
and this one is easier to bind.

Cheers

[1] cairo.h
cairo_image_surface_create_from_png_stream (cairo_read_func_t   
read_func, ...