Cache JumpList icons to avoid unnecessary creation and deletion

chrome/browser/win/jumplist_updater.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 CHROME_BROWSER_WIN_JUMPLIST_UPDATER_H_
 #define CHROME_BROWSER_WIN_JUMPLIST_UPDATER_H_
 
 #include <windows.h>
 #include <shobjidl.h>
 #include <stddef.h>
@@ skipping 10 matching lines @@
 // Represents a class used for creating an IShellLink object.
 // Even though an IShellLink also needs the absolute path to an application to
 // be executed, this class does not have any variables for it because current
 // users always use "chrome.exe" as the application.
 class ShellLinkItem : public base::RefCountedThreadSafe<ShellLinkItem> {
  public:
   ShellLinkItem();
 
   const base::string16& title() const { return title_; }
   const base::string16& icon_path() const { return icon_path_; }
+  const std::string& url() const { return url_; }
   int icon_index() const { return icon_index_; }
   const gfx::ImageSkia& icon_image() const { return icon_image_; }
 
   base::string16 GetArguments() const;
   base::CommandLine* GetCommandLine();
 
   void set_title(const base::string16& title) { title_ = title; }
-
   void set_icon(const base::string16& path, int index) {
     icon_path_ = path;
     icon_index_ = index;
   }
+  void set_url(const std::string& url) { url_ = url; }
 
   void set_icon_image(const gfx::ImageSkia& image) {
     icon_image_ = image;
   }
 
  private:
   friend class base::RefCountedThreadSafe<ShellLinkItem>;
   ~ShellLinkItem();
 
   // Used for storing and appending command-line arguments.
   base::CommandLine command_line_;
 
   // The string to be displayed in a JumpList.
   base::string16 title_;
 
   // The absolute path to an icon to be displayed in a JumpList.
   base::string16 icon_path_;
 
+  // The tab URL corresponding to this link's favicon.
+  std::string url_;
+
   // The icon index in the icon file. If an icon file consists of two or more
   // icons, set this value to identify the icon. If an icon file consists of
   // one icon, this value is 0.
   int icon_index_;
 
   // Icon image. Used by the browser JumpList.
   // Note that an icon path must be supplied to IShellLink, so users of this
   // class must save icon data to disk.
   gfx::ImageSkia icon_image_;
 
@@ skipping 59 matching lines @@
   base::win::ScopedComPtr<ICustomDestinationList> destination_list_;
 
   // The current user setting for "Number of recent items to display in Jump
   // Lists" option in the "Taskbar and Start Menu Properties".
   size_t user_max_items_;
 
   DISALLOW_COPY_AND_ASSIGN(JumpListUpdater);
 };
 
 #endif  // CHROME_BROWSER_WIN_JUMPLIST_UPDATER_H_