Fix object ownership in ui/base/models.

components/bookmarks/managed/managed_bookmarks_tracker.cc

Index: components/bookmarks/managed/managed_bookmarks_tracker.cc
diff --git a/components/bookmarks/managed/managed_bookmarks_tracker.cc b/components/bookmarks/managed/managed_bookmarks_tracker.cc
index b72a3c5db943688d1b1fb99dc34a094f44e8e839..7ff6f2b0caed8956542a84648acda54a7ce2efe7 100644
--- a/components/bookmarks/managed/managed_bookmarks_tracker.cc
+++ b/components/bookmarks/managed/managed_bookmarks_tracker.cc
@@ -60,9 +60,10 @@ int64_t ManagedBookmarksTracker::LoadInitial(BookmarkNode* folder,
     if (!LoadBookmark(list, i, &title, &url, &children))
       continue;
 
-    BookmarkNode* child = new BookmarkNode(next_node_id++, url);
+    BookmarkNode* child =
+        folder->Add(base::MakeUnique<BookmarkNode>(next_node_id++, url),
+                    folder->child_count());
     child->SetTitle(title);
-    folder->Add(child, folder->child_count());
     if (children) {
       child->set_type(BookmarkNode::FOLDER);
       child->set_date_folder_modified(base::Time::Now());