Extract Favicon Download logic from FaviconTabHelper

chrome/browser/favicon/favicon_tab_helper.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_FAVICON_FAVICON_TAB_HELPER_H_
 #define CHROME_BROWSER_FAVICON_FAVICON_TAB_HELPER_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
+#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
 #include "chrome/browser/favicon/favicon_handler_delegate.h"
 #include "chrome/browser/history/history_types.h"
 #include "chrome/common/favicon_url.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
 namespace gfx {
 class Image;
 }
 
 class GURL;
 class FaviconHandler;
 class Profile;
 class SkBitmap;
 
 // FaviconTabHelper works with FaviconHandlers to fetch the favicons.
 //
 // FetchFavicon fetches the given page's icons. It requests the icons from the
 // history backend. If the icon is not available or expired, the icon will be
 // downloaded and saved in the history backend.
 //
 // DownloadImage downloads the specified icon and returns it through the given
 // callback.
 //
 class FaviconTabHelper : public content::WebContentsObserver,
                          public FaviconHandlerDelegate,
+                         public FaviconDownloadHelperDelegate,
                          public content::WebContentsUserData<FaviconTabHelper> {
  public:
   virtual ~FaviconTabHelper();
 
   // Initiates loading the favicon for the specified url.
   void FetchFavicon(const GURL& url);
 
   // Returns the favicon for this tab, or IDR_DEFAULT_FAVICON if the tab does
   // not have a favicon. The default implementation uses the current navigation
   // entry. This will return an empty bitmap if there are no navigation
@@ skipping 40 matching lines @@
 
   // content::WebContentsObserver overrides.
   virtual void NavigateToPendingEntry(
       const GURL& url,
       content::NavigationController::ReloadType reload_type) OVERRIDE;
   virtual void DidNavigateMainFrame(
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
-  // Message handler for IconHostMsg_DidDownloadFavicon.
-  void OnDidDownloadFavicon(int id,
-                            const GURL& image_url,
-                            bool errored,
-                            int requested_size,
-                            const std::vector<SkBitmap>& bitmaps);
+  // FaviconDownloadHelperDelegate overrides.
+  virtual void OnDidDownloadFavicon(
+      int id,
+      const GURL& image_url,
+      bool errored,
+      int requested_size,
+      const std::vector<SkBitmap>& bitmaps) OVERRIDE;
 
   Profile* profile_;
 
   scoped_ptr<FaviconHandler> favicon_handler_;
 
   // Handles downloading touchicons. It is NULL if
   // browser_defaults::kEnableTouchIcon is false.
   scoped_ptr<FaviconHandler> touch_icon_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(FaviconTabHelper);
 };
 
 #endif  // CHROME_BROWSER_FAVICON_FAVICON_TAB_HELPER_H_