Make the HistoryMenuBridge::HistoryItem co-own the NSMenuItem. This hopefully fixes a top-crash.

chrome/browser/cocoa/history_menu_bridge_unittest.mm

 // Copyright (c) 2010 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 <Cocoa/Cocoa.h>
 #include <vector>
 
 #include "base/ref_counted_memory.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
@@ skipping 351 matching lines @@
 
   // Convert it to raw PNG bytes. We totally ignore color order here because
   // we just want to test the roundtrip through the Bridge, not that we can
   // make icons look pretty.
   std::vector<unsigned char> raw;
   gfx::PNGCodec::EncodeBGRASkBitmap(bitmap, true, &raw);
   scoped_refptr<RefCountedBytes> bytes(new RefCountedBytes(raw));
 
   // Set up the HistoryItem.
   HistoryMenuBridge::HistoryItem item;
-  scoped_nsobject<NSMenuItem> menu_item([[NSMenuItem alloc] init]);
-  item.menu_item = menu_item.get();
+  item.menu_item.reset([[NSMenuItem alloc] init]);
   GetFaviconForHistoryItem(&item);
 
   // Pretend to be called back.
   GotFaviconData(item.icon_handle, true, bytes, false, GURL());
 
   // Make sure the callback works.
   EXPECT_EQ(false, item.icon_requested);
   EXPECT_TRUE(item.icon.get());
   EXPECT_TRUE([item.menu_item image]);
 }
 
 }  // namespace