[gtk+] gadget: improve debug message

[Cosimo Cecchi <cosimoc src gnome org>]

commit 0fb50dc9a81d550a646bd9152d1fe38047525eda
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Sun Feb 28 14:52:14 2016 -0800

    gadget: improve debug message

 gtk/gtkcssgadget.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkcssgadget.c b/gtk/gtkcssgadget.c
index 2440879..d93075d 100644
--- a/gtk/gtkcssgadget.c
+++ b/gtk/gtkcssgadget.c
@@ -825,7 +825,9 @@ gtk_css_gadget_draw (GtkCssGadget *gadget,
   if (width < 0 || height < 0)
     {
       g_warning ("Drawing a gadget with negative dimensions. "
-                 "Did you forget to allocate a size?");
+                 "Did you forget to allocate a size? (node %s owner %s)",
+                 gtk_css_node_get_name (gtk_css_gadget_get_node (gadget)),
+                 G_OBJECT_TYPE_NAME (gtk_css_gadget_get_owner (gadget)));
       x = 0;
       y = 0;
       width = gtk_widget_get_allocated_width (priv->owner);