[gtk+] Inspector: Protect against childless windows

[Timm Bäder <baedert src gnome org>]

commit 571da2a8b34cf0652a0ba14adc35093b86631ea5
Author: Timm Bäder <mail baedert org>
Date:   Wed Aug 26 11:54:01 2015 +0200

    Inspector: Protect against childless windows

 gtk/inspector/inspect-button.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/gtk/inspector/inspect-button.c b/gtk/inspector/inspect-button.c
index b2cdfb5..c0df8de 100644
--- a/gtk/inspector/inspect-button.c
+++ b/gtk/inspector/inspect-button.c
@@ -405,10 +405,14 @@ draw_flash (GtkWidget          *widget,
 
   if (GTK_IS_WINDOW (widget))
     {
+      GtkWidget *child = gtk_bin_get_child (GTK_BIN (widget));
       /* We don't want to draw the drag highlight around the
        * CSD window decorations
        */
-      gtk_widget_get_allocation (gtk_bin_get_child (GTK_BIN (widget)), &alloc);
+      if (child == NULL)
+        return FALSE;
+
+      gtk_widget_get_allocation (child, &alloc);
     }
   else
     {