GTK: Another GTK deprecation patch.

chrome/browser/ui/gtk/tab_contents_container_gtk.cc

Index: chrome/browser/ui/gtk/tab_contents_container_gtk.cc
diff --git a/chrome/browser/ui/gtk/tab_contents_container_gtk.cc b/chrome/browser/ui/gtk/tab_contents_container_gtk.cc
index 48e45a947656605852976a6f25319d0070474349..20aa8d5c9d01cafd499f6b18a33ceaf878b033a4 100644
--- a/chrome/browser/ui/gtk/tab_contents_container_gtk.cc
+++ b/chrome/browser/ui/gtk/tab_contents_container_gtk.cc
@@ -165,9 +165,12 @@ void TabContentsContainerGtk::DetachTab(TabContentsWrapper* tab) {
 
   // It is possible to detach an unrealized, unparented TabContents if you
   // slow things down enough in valgrind. Might happen in the real world, too.
-  if (widget && widget->parent) {
-    DCHECK_EQ(widget->parent, expanded_);
-    gtk_container_remove(GTK_CONTAINER(expanded_), widget);
+  if (widget) {
+    GtkWidget* parent = gtk_widget_get_parent(widget);
+    if (parent) {
+      DCHECK_EQ(parent, expanded_);
+      gtk_container_remove(GTK_CONTAINER(expanded_), widget);
+    }
   }
 }