[gtk] Remove an outdated comment

[Matthias Clasen <matthiasc src gnome org>]

commit 8f95a5980e739f84392967baed3b8c654a0cbab8
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jul 29 08:45:34 2018 -0400

    Remove an outdated comment
    
    We no longer have semi-private headers.

 gtk/gtktextdisplay.c | 4 ----
 1 file changed, 4 deletions(-)
---
diff --git a/gtk/gtktextdisplay.c b/gtk/gtktextdisplay.c
index 2b9e88f80e..4e6c49fd16 100644
--- a/gtk/gtktextdisplay.c
+++ b/gtk/gtktextdisplay.c
@@ -81,10 +81,6 @@
 #include "gtkintl.h"
 #include <gdk/gdktextureprivate.h>
 
-/* DO NOT go putting private headers in here. This file should only
- * use the semi-public headers, as with gtktextview.c.
- */
-
 #define GTK_TYPE_TEXT_RENDERER            (_gtk_text_renderer_get_type())
 #define GTK_TEXT_RENDERER(object)         (G_TYPE_CHECK_INSTANCE_CAST ((object), GTK_TYPE_TEXT_RENDERER, 
GtkTextRenderer))
 #define GTK_IS_TEXT_RENDERER(object)      (G_TYPE_CHECK_INSTANCE_TYPE ((object), GTK_TYPE_TEXT_RENDERER))