[goffice] Canvas: fix another crash.

[Morten Welinder <mortenw src gnome org>]

commit 1c12efbbe1cb9c9615f046c1c7d928abf39742b2
Author: Morten Welinder <terra gnome org>
Date:   Thu Sep 17 12:24:25 2009 -0400

    Canvas: fix another crash.

 ChangeLog                 |   11 +++++++++--
 goffice/canvas/goc-item.c |    6 +++++-
 2 files changed, 14 insertions(+), 3 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index f4982ef..60c8158 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,12 +1,19 @@
 2009-09-18  Jean Brefort  <jean brefort normalesup org>
 
 	* docs/reference/goffice-0.8-sections.txt: removed duplicates
-	* goffice/canvas/goc-group.c (goc_group_draw_region): remove unuseful call.
-	* goffice/canvas/goc-item.c: update documentation and remove unused code.
+	* goffice/canvas/goc-group.c (goc_group_draw_region): remove unuseful
+	call.
+	* goffice/canvas/goc-item.c: update documentation and remove unused
+	code.
 	* goffice/canvas/goc-item.h: remove unused fields.
 	* goffice/gtk/goffice-gtk.c: add missing colons.
 	* goffice/utils/go-style.c: fixed a documentation warning.
 
+2009-09-17  Morten Welinder  <terra gnome org>
+
+	* goffice/canvas/goc-item.c (goc_item_invalidate): Handle the
+	no-parent case without crashing.
+
 2009-09-16  Morten Welinder  <terra gnome org>
 
 	* goffice/canvas/goc-widget.c (goc_widget_init,
diff --git a/goffice/canvas/goc-item.c b/goffice/canvas/goc-item.c
index dac107d..4a6340c 100644
--- a/goffice/canvas/goc-item.c
+++ b/goffice/canvas/goc-item.c
@@ -311,10 +311,14 @@ goc_item_invalidate (GocItem *item)
 	double x0, y0, x1, y1;
 
 	g_return_if_fail (GOC_IS_ITEM (item));
+
+	parent = item->parent;
+	if (!parent)
+		return;
+
 	if (!GTK_WIDGET_REALIZED (item->canvas))
 		return;
 
-	parent = item->parent;
 	if (!item->cached_bounds)
 		goc_item_update_bounds (GOC_ITEM (item)); /* don't care about const */
 	x0 = item->x0;