Function gio_2_0_sys::g_proxy_resolver_lookup_async

pub unsafe extern "C" fn g_proxy_resolver_lookup_async(
    resolver: *mut GProxyResolver, 
    uri: *const gchar, 
    cancellable: *mut GCancellable, 
    callback: Option<GAsyncReadyCallback>, 
    user_data: gpointer
)