Mac BookmarkBubbleController updateBookmarkNode crash.

chrome/browser/cocoa/bookmark_bubble_controller.mm

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/cocoa/bookmark_bubble_controller.h"
 #include "app/l10n_util_mac.h"
 #include "base/mac_util.h"
 #include "base/sys_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #import "chrome/browser/cocoa/browser_window_controller.h"
@@ skipping 175 matching lines @@
   UserMetrics::RecordAction(UserMetricsAction("BookmarkBubble_Unstar"),
                             model_->profile());
   node_ = NULL;  // no longer valid
   [self ok:sender];
 }
 
 // The controller is  the target of the pop up button box action so it can
 // handle when "choose another folder" was picked.
 - (IBAction)folderChanged:(id)sender {
   DCHECK([sender isEqual:folderPopUpButton_]);
+  // It is possible that due to model change our parent window has been closed
+  // but the popup is still showing and able to notify the controller of a
+  // folder change.  We ignore the sender in this case.
+  if (!parentWindow_)
+    return;
   NSMenuItem* selected = [folderPopUpButton_ selectedItem];
   ChooseAnotherFolder* chooseItem = [[self class] chooseAnotherFolderObject];
   if ([[selected representedObject] isEqual:chooseItem]) {
     UserMetrics::RecordAction(
         UserMetricsAction("BookmarkBubble_EditFromCombobox"),
         model_->profile());
     [self showEditor];
   }
 }
 
@@ skipping 112 matching lines @@
   NSInteger idx = [menu indexOfItemWithRepresentedObject:parentValue];
   DCHECK(idx != -1);
   [folderPopUpButton_ selectItemAtIndex:idx];
 }
 
 - (NSPopUpButton*)folderPopUpButton {
   return folderPopUpButton_;
 }
 
 @end  // implementation BookmarkBubbleController(ExposedForUnitTesting)