Avoid conversion of index to BookmarkNode pointer unnacessarily.

components/bookmarks/browser/bookmark_model.h

 // Copyright 2014 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.
 
 #ifndef COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_MODEL_H_
 #define COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_MODEL_H_
 
 #include <map>
 #include <set>
 #include <vector>
@@ skipping 109 matching lines @@
   // until it's finished.
   void BeginExtensiveChanges();
   void EndExtensiveChanges();
 
   // Returns true if this bookmark model is currently in a mode where extensive
   // changes might happen, such as for import and sync. This is helpful for
   // observers that are created after the mode has started, and want to check
   // state during their own initializer, such as the NTP.
   bool IsDoingExtensiveChanges() const { return extensive_changes_ > 0; }
 
-  // Removes the node at the given |index| from |parent|. Removing a folder node
-  // recursively removes all nodes. Observers are notified immediately.
-  void Remove(const BookmarkNode* parent, int index);
+  // Removes the child node. Removing a folder node recursively removes all
+  // nodes. Observers are notified immediately.
+  void Remove(const BookmarkNode* parent, const BookmarkNode* child);

[sky, 2015/04/29 15:26:27]

If you're going to clean this code up, there is no point in supplying parent.
You can get the parent from child.

 
   // Removes all the non-permanent bookmark nodes that are editable by the user.
   // Observers are only notified when all nodes have been removed. There is no
   // notification for individual node removals.
   void RemoveAllUserBookmarks();
 
   // Moves |node| to |new_parent| and inserts it at the given |index|.
   void Move(const BookmarkNode* node,
             const BookmarkNode* new_parent,
             int index);
@@ skipping 299 matching lines @@
   scoped_ptr<BookmarkExpandedStateTracker> expanded_state_tracker_;
 
   std::set<std::string> non_cloned_keys_;
 
   DISALLOW_COPY_AND_ASSIGN(BookmarkModel);
 };
 
 }  // namespace bookmarks
 
 #endif  // COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_MODEL_H_