[gtk+] Improve doc of gtk_style_context_invalidate()

[Benjamin Otte <otte src gnome org>]

commit ab112a2096288fabe7162009bfff02cad028c530
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sat Sep 28 16:19:07 2013 +0200

    Improve doc of gtk_style_context_invalidate()
    
    https://bugzilla.gnome.org/show_bug.cgi?id=708583

 gtk/gtkstylecontext.c |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)
---
diff --git a/gtk/gtkstylecontext.c b/gtk/gtkstylecontext.c
index cf7ea20..d45157d 100644
--- a/gtk/gtkstylecontext.c
+++ b/gtk/gtkstylecontext.c
@@ -3382,11 +3382,8 @@ _gtk_style_context_queue_invalidate (GtkStyleContext *context,
  * @context: a #GtkStyleContext.
  *
  * Invalidates @context style information, so it will be reconstructed
- * again.
- *
- * If you're using a #GtkStyleContext returned from
- * gtk_widget_get_style_context(), you do not need to
- * call this yourself.
+ * again. It is useful if you modify the @context and need the new
+ * information immediately.
  *
  * Since: 3.0
  **/