[gtk/matthiasc/for-master: 4/4] gtk-demo: Add a warning to the colors demo

[Matthias Clasen <matthiasc src gnome org>]

commit 9fd321224153a3cdafc8b6b4c2699c8e4e86876b
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jun 22 07:43:47 2020 -0400

    gtk-demo: Add a warning to the colors demo
    
    Explain that the big sizes cause lockups.

 demos/gtk-demo/listview_colors.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/demos/gtk-demo/listview_colors.c b/demos/gtk-demo/listview_colors.c
index 37034abf78..9c3841f6a5 100644
--- a/demos/gtk-demo/listview_colors.c
+++ b/demos/gtk-demo/listview_colors.c
@@ -1,12 +1,17 @@
 /* Lists/Colors
  *
- * This demo displays a list of named colors.
+ * This demo displays a grid of colors.
  *
  * It is using a GtkGridView, and shows how to display
  * and sort the data in various ways. The controls for
  * this are implemented using GtkDropDown.
  *
- * The dataset used here has 9 283 items.
+ * The dataset used here has up to 16 777 216 items.
+ *
+ * Note that this demo also functions as a performance
+ * test for some of the list model machinery, and biggest
+ * sizes here can lock up the application for extended
+ * times when used with sorting.
  */
 
 #include <gtk/gtk.h>