app: don't rely on gtk_container_remove() to always destroy the child

Instead, either destroy the child instead of removing it, or remove
*and* destroy it in cases where the remove() api on the "parent"
doesn't match GTK+'s parent/child relation (like with all our dock
widgets). We can't rely on remove() to implicitly detstroy, because
there might be arbitrary other code holding references, such as
accessibility modules and whatnot. Most likely fixes unclear crashes
in accessibility code and other crashes we blamed GTK+ for.

app/actions/dockable-commands.c

@@ -62,7 +62,12 @@ dockable_close_tab_cmd_callback (GtkAction *action,
   GimpDockable *dockable = dockable_get_current (dockbook);
 
   if (dockable)
-    gimp_dockbook_remove (dockbook, dockable);
+    {
+      g_object_ref (dockable);
+      gimp_dockbook_remove (dockbook, dockable);
+      gtk_widget_destroy (GTK_WIDGET (dockable));
+      g_object_unref (dockable);
+    }
 }
 
 void
@@ -188,7 +193,10 @@ dockable_toggle_view_cmd_callback (GtkAction *action,
                       gimp_dockbook_add (dockbook, GIMP_DOCKABLE (new_dockable),
                                          page_num);
 
+                      g_object_ref (dockable);
                       gimp_dockbook_remove (dockbook, dockable);
+                      gtk_widget_destroy (GTK_WIDGET (dockable));
+                      g_object_unref (dockable);
 
                       gtk_notebook_set_current_page (GTK_NOTEBOOK (dockbook),
                                                      page_num);

app/display/gimpimagewindow.c

@@ -425,21 +425,6 @@ gimp_image_window_constructed (GObject *object)
                                     gimp_image_window_config_to_entry_id (config));
 }
 
-static void
-gimp_image_window_clear_docks (GimpDockColumns *columns)
-{
-  GList *docks;
-
-  do
-    {
-      docks = gimp_dock_columns_get_docks (columns);
-
-      if (docks)
-        gimp_dock_columns_remove_dock (columns, docks->data);
-    }
-  while (docks);
-}
-
 static void
 gimp_image_window_dispose (GObject *object)
 {
@@ -459,18 +444,6 @@ gimp_image_window_dispose (GObject *object)
       private->menubar_manager = NULL;
     }
 
-  if (private->left_docks)
-    {
-      gimp_image_window_clear_docks (GIMP_DOCK_COLUMNS (private->left_docks));
-      private->left_docks = NULL;
-    }
-
-  if (private->right_docks)
-    {
-      gimp_image_window_clear_docks (GIMP_DOCK_COLUMNS (private->right_docks));
-      private->right_docks = NULL;
-    }
-
   G_OBJECT_CLASS (parent_class)->dispose (object);
 }
 

app/tools/gimpgegltool.c

@@ -679,8 +679,7 @@ gimp_gegl_tool_operation_changed (GtkWidget    *widget,
 
   if (tool->options_table)
     {
-      gtk_container_remove (GTK_CONTAINER (tool->options_frame),
-                            tool->options_table);
+      gtk_widget_destroy (tool->options_table);
       tool->options_table = NULL;
     }
 

app/widgets/gimpcontainergridview.c

@@ -469,7 +469,7 @@ gimp_container_grid_view_remove_item (GimpContainerView *container_view,
   if (view == (GtkWidget *) grid_view->selected_item)
     grid_view->selected_item = NULL;
 
-  gtk_container_remove (GTK_CONTAINER (grid_view->wrap_box), view);
+  gtk_widget_destroy (view);
 }
 
 static void
@@ -520,8 +520,7 @@ gimp_container_grid_view_clear_items (GimpContainerView *view)
   grid_view->selected_item = NULL;
 
   while (GTK_WRAP_BOX (grid_view->wrap_box)->children)
-    gtk_container_remove (GTK_CONTAINER (grid_view->wrap_box),
-                          GTK_WRAP_BOX (grid_view->wrap_box)->children->widget);
+    gtk_widget_destroy (GTK_WRAP_BOX (grid_view->wrap_box)->children->widget);
 
   parent_view_iface->clear_items (view);
 }

app/widgets/gimpcontainerpopup.c

@@ -499,8 +499,7 @@ gimp_container_popup_set_view_type (GimpContainerPopup *popup,
     {
       popup->view_type = view_type;
 
-      gtk_container_remove (GTK_CONTAINER (popup->frame),
-                            GTK_WIDGET (popup->editor));
+      gtk_widget_destroy (GTK_WIDGET (popup->editor));
       gimp_container_popup_create_view (popup);
     }
 }

app/widgets/gimpdock.c

@@ -201,7 +201,14 @@ gimp_dock_dispose (GObject *object)
   GimpDock *dock = GIMP_DOCK (object);
 
   while (dock->p->dockbooks)
-    gimp_dock_remove_book (dock, GIMP_DOCKBOOK (dock->p->dockbooks->data));
+    {
+      GimpDockbook *dockbook = dock->p->dockbooks->data;
+
+      g_object_ref (dockbook);
+      gimp_dock_remove_book (dock, dockbook);
+      gtk_widget_destroy (GTK_WIDGET (dockbook));
+      g_object_unref (dockbook);
+    }
 
   G_OBJECT_CLASS (parent_class)->dispose (object);
 }

app/widgets/gimpdockbook.c

@@ -304,7 +304,14 @@ gimp_dockbook_dispose (GObject *object)
   gimp_dockbook_remove_tab_timeout (dockbook);
 
   while (dockbook->p->dockables)
-    gimp_dockbook_remove (dockbook, dockbook->p->dockables->data);
+    {
+      GimpDockable *dockable = dockbook->p->dockables->data;
+
+      g_object_ref (dockable);
+      gimp_dockbook_remove (dockbook, dockable);
+      gtk_widget_destroy (GTK_WIDGET (dockable));
+      g_object_unref (dockable);
+    }
 
   G_OBJECT_CLASS (parent_class)->dispose (object);
 }
@@ -1586,7 +1593,7 @@ static GtkIconSize
 gimp_dockbook_get_tab_icon_size (GimpDockbook *dockbook)
 {
   GtkIconSize tab_size = DEFAULT_TAB_ICON_SIZE;
-  
+
   gtk_widget_style_get (GTK_WIDGET (dockbook),
                         "tab-icon-size", &tab_size,
                         NULL);

app/widgets/gimpdockcolumns.c

@@ -179,7 +179,14 @@ gimp_dock_columns_dispose (GObject *object)
   GimpDockColumns *dock_columns = GIMP_DOCK_COLUMNS (object);
 
   while (dock_columns->p->docks)
-    gimp_dock_columns_remove_dock (dock_columns, dock_columns->p->docks->data);
+    {
+      GimpDock *dock = dock_columns->p->docks->data;
+
+      g_object_ref (dock);
+      gimp_dock_columns_remove_dock (dock_columns, dock);
+      gtk_widget_destroy (GTK_WIDGET (dock));
+      g_object_unref (dock);
+    }
 
   G_OBJECT_CLASS (parent_class)->dispose (object);
 }

app/widgets/gimpeditor.c

@@ -656,7 +656,7 @@ gimp_editor_add_action_button (GimpEditor  *editor,
   old_child = gtk_bin_get_child (GTK_BIN (button));
 
   if (old_child)
-    gtk_container_remove (GTK_CONTAINER (button), old_child);
+    gtk_widget_destroy (old_child);
 
   image = gtk_image_new_from_stock (stock_id, button_icon_size);
   gtk_container_add (GTK_CONTAINER (button), image);

app/widgets/gimppanedbox.c

@@ -168,7 +168,14 @@ gimp_paned_box_dispose (GObject *object)
   GimpPanedBox *paned_box = GIMP_PANED_BOX (object);
 
   while (paned_box->p->widgets)
-    gimp_paned_box_remove_widget (paned_box, paned_box->p->widgets->data);
+    {
+      GtkWidget *widget = paned_box->p->widgets->data;
+
+      g_object_ref (widget);
+      gimp_paned_box_remove_widget (paned_box, widget);
+      gtk_widget_destroy (widget);
+      g_object_unref (widget);
+    }
 
   G_OBJECT_CLASS (parent_class)->dispose (object);
 }

app/widgets/gimpsessioninfo-dock.c

@@ -347,7 +347,11 @@ gimp_session_info_dock_restore (GimpSessionInfoDock *dock_info,
             }
           else
             {
+              g_object_ref (dockbook);
               gimp_dock_remove_book (GIMP_DOCK (dock), GIMP_DOCKBOOK (dockbook));
+              gtk_widget_destroy (GTK_WIDGET (dockbook));
+              g_object_unref (dockbook);
+
               n_books--;
             }