[gnumeric] Fixed crash with sheet object. [#671617]

[Jean BrÃfort <jbrefort src gnome org>]

commit c3f1c262dd9a85896d62ff125e22b6abedc97f1a
Author: Jean Brefort <jean brefort normalesup org>
Date:   Thu Mar 8 11:10:47 2012 +0100

    Fixed crash with sheet object. [#671617]

 ChangeLog                 |    5 +++++
 NEWS                      |    3 +++
 src/sheet-object-widget.c |    4 ++--
 3 files changed, 10 insertions(+), 2 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index ea56437..0dae147 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2012-03-08  Jean Brefort  <jean brefort normalesup org>
+
+	* src/sheet-object-widget.c (widget_wbc), (cb_selection_changed): fixed
+	crash with sheet object. [#671617]
+
 2012-03-07  Morten Welinder  <terra gnome org>
 
 	* plugins/excel/ms-excel-read.c (excel_read_LABEL): supply the
diff --git a/NEWS b/NEWS
index 592eef2..ad03653 100644
--- a/NEWS
+++ b/NEWS
@@ -6,6 +6,9 @@ Andreas:
 	* On ODF import set series to default to ignoring invalids for interpolation.
 	[#671508]
 
+Jean:
+	* Fixed crash with sheet object. [#671617]
+
 Morten:
 	* Hook up unknown_image icon for ssconvert too.
 	* Fix xls save crash.  [#671267]
diff --git a/src/sheet-object-widget.c b/src/sheet-object-widget.c
index 64b48fb..7418eb9 100644
--- a/src/sheet-object-widget.c
+++ b/src/sheet-object-widget.c
@@ -331,7 +331,7 @@ static GSF_CLASS (SheetObjectWidget, sheet_object_widget,
 static WorkbookControl *
 widget_wbc (GtkWidget *widget)
 {
-	return scg_wbc (GNM_SIMPLE_CANVAS (gtk_widget_get_parent (gtk_widget_get_parent (widget)))->scg);
+	return scg_wbc (GNM_SIMPLE_CANVAS (gtk_widget_get_ancestor (widget, GNM_SIMPLE_CANVAS_TYPE))->scg);
 }
 
 
@@ -3300,7 +3300,7 @@ cb_selection_changed (GtkTreeSelection *selection,
 		      SheetWidgetListBase *swl)
 {
 	GtkWidget    *view = (GtkWidget *)gtk_tree_selection_get_tree_view (selection);
-	GnmSimpleCanvas *scanvas = GNM_SIMPLE_CANVAS (gtk_widget_get_parent (gtk_widget_get_parent (gtk_widget_get_parent (view))));
+	GnmSimpleCanvas *scanvas = GNM_SIMPLE_CANVAS (gtk_widget_get_ancestor (view, GNM_SIMPLE_CANVAS_TYPE));
 	GtkTreeModel *model;
 	GtkTreeIter   iter;
 	int	      pos = 0;