[gtk+] Improve unsetting old buffer in gtk_text_view_set_buffer()

[Kristian Rietveld <kristian src gnome org>]

commit dc3fb714a08a102c0972489afd0c566b9a17cc56
Author: Kristian Rietveld <kris gtk org>
Date:   Fri Sep 4 13:41:17 2009 +0200

    Improve unsetting old buffer in gtk_text_view_set_buffer()
    
    When unsetting the old buffer always set the buffer on the layout to
    NULL.  More importantly, clear the pending scroll.  (The scroll is
    handled in an idle, when not cleared an idle handler might touch the
    layout later on, possibly corrupting the BTree).  Unref the buffer after
    removing the selection from the clipboard, not before.  Patch merged
    from maemo-gtk.

 gtk/gtktextview.c |   14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)
---
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index ad04480..72d7fe3 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -349,6 +349,7 @@ static GtkAdjustment* get_vadjustment            (GtkTextView       *text_view);
 static void gtk_text_view_do_popup               (GtkTextView       *text_view,
 						  GdkEventButton    *event);
 
+static void cancel_pending_scroll                (GtkTextView   *text_view);
 static void gtk_text_view_queue_scroll           (GtkTextView   *text_view,
                                                   GtkTextMark   *mark,
                                                   gdouble        within_margin,
@@ -1412,16 +1413,21 @@ gtk_text_view_set_buffer (GtkTextView   *text_view,
       g_signal_handlers_disconnect_by_func (text_view->buffer,
                                             gtk_text_view_paste_done_handler,
                                             text_view);
-      g_object_unref (text_view->buffer);
-      text_view->dnd_mark = NULL;
-      text_view->first_para_mark = NULL;
 
       if (GTK_WIDGET_REALIZED (text_view))
 	{
 	  GtkClipboard *clipboard = gtk_widget_get_clipboard (GTK_WIDGET (text_view),
 							      GDK_SELECTION_PRIMARY);
 	  gtk_text_buffer_remove_selection_clipboard (text_view->buffer, clipboard);
-	}
+        }
+
+      if (text_view->layout)
+        gtk_text_layout_set_buffer (text_view->layout, NULL);
+
+      g_object_unref (text_view->buffer);
+      text_view->dnd_mark = NULL;
+      text_view->first_para_mark = NULL;
+      cancel_pending_scroll (text_view);
     }
 
   text_view->buffer = buffer;