Reduce the memory usage of bookmarks storage

components/bookmarks/browser/bookmark_node.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_NODE_H_
 #define COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_NODE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 51 matching lines @@
   // For bookmark nodes that are managed by the bookmark model, the IDs are
   // persisted across sessions.
   int64_t id() const { return id_; }
   void set_id(int64_t id) { id_ = id; }
 
   const GURL& url() const { return url_; }
   void set_url(const GURL& url) { url_ = url; }
 
   // Returns the favicon's URL. Returns an empty URL if there is no favicon
   // associated with this bookmark.
-  const GURL& icon_url() const { return icon_url_; }
+  const GURL* icon_url() const { return icon_url_ ? icon_url_.get() : nullptr; }
 
   Type type() const { return type_; }
   void set_type(Type type) { type_ = type; }
 
   // Returns the time the node was added.
   const base::Time& date_added() const { return date_added_; }
   void set_date_added(const base::Time& date) { date_added_ = date; }
 
   // Returns the last time the folder was modified. This is only maintained
   // for folders (including the bookmark bar and other folder).
@@ skipping 44 matching lines @@
   friend class BookmarkModel;
 
   // A helper function to initialize various fields during construction.
   void Initialize(int64_t id);
 
   // Called when the favicon becomes invalid.
   void InvalidateFavicon();
 
   // Sets the favicon's URL.
   void set_icon_url(const GURL& icon_url) {
-    icon_url_ = icon_url;
+    icon_url_.reset(new GURL(icon_url));

[sky, 2017/05/31 22:35:49]

Use MakeUnique (in base/memory/ptr_util.h) (see threads on chormium-dev for the
why).

[ssid, 2017/06/01 01:26:29]

Done.

   }
 
   // Returns the favicon. In nearly all cases you should use the method
   // BookmarkModel::GetFavicon rather than this one as it takes care of
   // loading the favicon if it isn't already loaded.
   const gfx::Image& favicon() const { return favicon_; }
   void set_favicon(const gfx::Image& icon) { favicon_ = icon; }
 
   favicon_base::IconType favicon_type() const { return favicon_type_; }
   void set_favicon_type(favicon_base::IconType type) { favicon_type_ = type; }
@@ skipping 24 matching lines @@
   // Date of the last modification. Only used for folders.
   base::Time date_folder_modified_;
 
   // The favicon of this node.
   gfx::Image favicon_;
 
   // The type of favicon currently loaded.
   favicon_base::IconType favicon_type_;
 
   // The URL of the node's favicon.
-  GURL icon_url_;
+  std::unique_ptr<GURL> icon_url_;
 
   // The loading state of the favicon.
   FaviconState favicon_state_;
 
   // If not base::CancelableTaskTracker::kBadTaskId, it indicates
   // we're loading the
   // favicon and the task is tracked by CancelabelTaskTracker.
   base::CancelableTaskTracker::TaskId favicon_load_task_id_;
 
   // A map that stores arbitrary meta information about the node.
@@ skipping 21 matching lines @@
 
  private:
   bool visible_;
 
   DISALLOW_COPY_AND_ASSIGN(BookmarkPermanentNode);
 };
 
 }  // namespace bookmarks
 
 #endif  // COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_NODE_H_