Don't request missing favicon on every page request.

chrome/browser/ui/extensions/shell_window.h

 // Copyright (c) 2012 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_UI_EXTENSIONS_SHELL_WINDOW_H_
 #define CHROME_BROWSER_UI_EXTENSIONS_SHELL_WINDOW_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/extensions/extension_keybinding_registry.h"
@@ skipping 251 matching lines @@
       GetActiveTabPermissionGranter() OVERRIDE;
 
   // WebContentsModalDialogManagerDelegate implementation.
   virtual void SetWebContentsBlocked(content::WebContents* web_contents,
                                      bool blocked) OVERRIDE;
 
   virtual WebContentsModalDialogHost* GetWebContentsModalDialogHost() OVERRIDE;
 
   // Callback from web_contents()->DownloadFavicon.
   void DidDownloadFavicon(int id,
+                          int http_status_code,
                           const GURL& image_url,
                           int requested_size,
                           const std::vector<SkBitmap>& bitmaps);
 
   Profile* profile_;  // weak pointer - owned by ProfileManager.
   // weak pointer - owned by ExtensionService.
   const extensions::Extension* extension_;
   const std::string extension_id_;
 
   // Identifier that is used when saving and restoring geometry for this
@@ skipping 18 matching lines @@
 
   // Fullscreen entered by app.window api.
   bool fullscreen_for_window_api_;
   // Fullscreen entered by HTML requestFullscreen.
   bool fullscreen_for_tab_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellWindow);
 };
 
 #endif  // CHROME_BROWSER_UI_EXTENSIONS_SHELL_WINDOW_H_