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

chrome/browser/cookies_tree_model.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/cookies_tree_model.h"
 
 #include <algorithm>
 #include <functional>
 #include <vector>
 
@@ skipping 690 matching lines @@
   NotifyObserverTreeNodeChanged(root);
   NotifyObserverEndBatch();
 }
 
 void CookiesTreeModel::DeleteCookieNode(CookieTreeNode* cookie_node) {
   if (cookie_node == GetRoot())
     return;
   cookie_node->DeleteStoredObjects();
   CookieTreeNode* parent_node = cookie_node->parent();
   delete Remove(parent_node, cookie_node);
-  if (parent_node->child_count() == 0)
+  if (parent_node->empty())
     DeleteCookieNode(parent_node);
 }
 
 void CookiesTreeModel::UpdateSearchResults(const std::wstring& filter) {
   CookieTreeNode* root = GetRoot();
   int num_children = root->child_count();
   NotifyObserverBeginBatch();
   for (int i = num_children - 1; i >= 0; --i)
     delete Remove(root, root->GetChild(i));
   LoadCookiesWithFilter(filter);
@@ skipping 231 matching lines @@
 
 void CookiesTreeModel::NotifyObserverEndBatch() {
   // Only notify the observers if this is the outermost call to EndBatch() if
   // called in a nested manner.
   if (--batch_update_ == 0) {
     FOR_EACH_OBSERVER(Observer,
                       cookies_observer_list_,
                       TreeModelEndBatch(this));
   }
 }