[cairo] return type of cairo_status_to_string ()

[Bill Spitzak]

Daniel Goldman wrote:

>  I know that the const keyword will not allow you to assign twice 
> to error_str.

That is incorrect. You can assign to error_str many times:

	const char* error_str;
	error_str = "A";
	error_str = "B";

What you can't do is assign to what error_str points at:

	error_str[0] = 'x'; // will not compile!