[gnome-desktop] rr-labeler: clear surface before drawing frame and background

[Cosimo Cecchi <cosimoc src gnome org>]

commit 41a1074e4dd99e3b52e58a770cb8f7343aae8586
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Tue Sep 25 15:53:16 2012 -0400

    rr-labeler: clear surface before drawing frame and background
    
    To avoid gray areas extending below the edges.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=684814

 libgnome-desktop/gnome-rr-labeler.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/libgnome-desktop/gnome-rr-labeler.c b/libgnome-desktop/gnome-rr-labeler.c
index 3dcf0f4..918e106 100644
--- a/libgnome-desktop/gnome-rr-labeler.c
+++ b/libgnome-desktop/gnome-rr-labeler.c
@@ -279,6 +279,10 @@ label_window_draw_event_cb (GtkWidget *widget, cairo_t *cr, gpointer data)
 
 	cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
 
+	/* clear any content */
+	cairo_set_source_rgba (cr, 0, 0, 0, 0);
+	cairo_paint (cr);
+
 	/* edge outline */
 	cairo_set_source_rgba (cr, 0, 0, 0, 0.5);
 	rounded_rectangle (cr,