[goocanvas] gtk4: GooCanvas: Remove use of gtk_cairo_should_draw_window().

[Murray Cumming <murrayc src gnome org>]

commit d30d126777054f8c85cbc97b5f784dc148fdf096
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Dec 15 14:43:06 2016 +0100

    gtk4: GooCanvas: Remove use of gtk_cairo_should_draw_window().
    
    This suggests that it was useless anyway:
    https://mail.gnome.org/archives/commits-list/2016-October/msg07687.html

 src/goocanvas.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)
---
diff --git a/src/goocanvas.c b/src/goocanvas.c
index 51c1448..10bc629 100644
--- a/src/goocanvas.c
+++ b/src/goocanvas.c
@@ -2711,9 +2711,6 @@ goo_canvas_draw (GtkWidget      *widget,
   GooCanvasBounds clip_bounds, bounds, root_item_bounds;
   double x1, y1, x2, y2;
 
-  if (!gtk_cairo_should_draw_window (cr, canvas->canvas_window))
-    return FALSE;
-
   if (!canvas->root_item)
     {
       canvas->before_initial_draw = FALSE;