gtk: Add gtk_is_initialized() and gtk_get_main_thread()
These two functions are be useful, especially for gtk-rs, which performs some additional checks to ensure GTK+ is only used from the thread that called gtk_init().
Edited by Matthias Clasen
These two functions are be useful, especially for gtk-rs, which performs some additional checks to ensure GTK+ is only used from the thread that called gtk_init().