[Mac] Show context menu on empty BMB item.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_view.mm

 // Copyright (c) 2011 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/ui/cocoa/bookmarks/bookmark_bar_view.h"
 
 #include "chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h"
 #include "chrome/browser/profiles/profile.h"
 #import "chrome/browser/themes/theme_properties.h"
 #import "chrome/browser/themes/theme_service.h"
@@ skipping 244 matching lines @@
     // Fall through....
   }
   if ([pboard containsURLData]) {
     if ([self performDragOperationForURL:info])
       return YES;
   }
   return NO;
 }
 
 - (NSMenu*)menu {
-  return [[controller_ menuController] menuForBookmarkNode:NULL];
+  return [[controller_ menuController] menuForBookmarkBar];
 }
 
 - (void)setController:(id)controller {
   controller_ = controller;
 }
 
 - (ViewID)viewID {
   return VIEW_ID_BOOKMARK_BAR;
 }
 
 @end  // @implementation BookmarkBarView
 
 @implementation BookmarkBarTextField
 
 - (NSMenu*)menu {
   return [barView_ menu];
 }
 
 @end  // @implementation BookmarkBarTextField
 
 @implementation BookmarkBarItemContainer
 
 - (NSMenu*)menu {
   return [barView_ menu];
 }
 
 @end  // @implementation BookmarkBarItemContainer