ui/base/models: Add empty() accessor to TreeNode class.

chrome/browser/extensions/extension_bookmark_helpers.cc

 // 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.
 
 #include "chrome/browser/extensions/extension_bookmark_helpers.h"
 
 #include "base/string_number_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/extensions/extension_bookmarks_module_constants.h"
@@ skipping 81 matching lines @@
     *error = keys::kNoNodeError;
     return false;
   }
   if (node == model->root_node() ||
       node == model->other_node() ||
       node == model->synced_node() ||
       node == model->GetBookmarkBarNode()) {
     *error = keys::kModifySpecialError;
     return false;
   }
-  if (node->is_folder() && node->child_count() > 0 && !recursive) {
+  if (node->is_folder() && !node->empty() && !recursive) {
     *error = keys::kFolderNotEmptyError;
     return false;
   }
 
   const BookmarkNode* parent = node->parent();
   int index = parent->GetIndexOf(node);
   model->Remove(parent, index);
   return true;
 }
 
 }