Add Observer in 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 "base/observer_list.h"
 #include "components/favicon/core/browser/favicon_client.h"
 #include "components/favicon/core/favicon_driver.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 #include "content/public/common/favicon_url.h"
 
 namespace gfx {
 class Image;
 }
 
 namespace content {
 struct FaviconStatus;
 }
 
 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.
 //
 class FaviconTabHelper : public content::WebContentsObserver,
                          public FaviconDriver,
                          public content::WebContentsUserData<FaviconTabHelper> {
  public:
+  class Observer {
+   public:
+    // Called when favicon |image| is retrieved from either web site or history
+    // backend.
+    virtual void OnFaviconAvailable(const gfx::Image& image) = 0;
+  };
+
   ~FaviconTabHelper() override;
 
   // 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
   // entries, which should rarely happen.
   gfx::Image GetFavicon() const;
@@ skipping 12 matching lines @@
   }
 
   // content::WebContentsObserver override. Must be public, because also
   // called from PrerenderContents.
   void DidUpdateFaviconURL(
       const std::vector<content::FaviconURL>& candidates) override;
 
   // Saves the favicon for the current page.
   void SaveFavicon();
 
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
   // FaviconDriver methods.
   int StartDownload(const GURL& url, int max_bitmap_size) override;
-  void NotifyFaviconUpdated(bool icon_url_changed) override;
   bool IsOffTheRecord() override;
   const gfx::Image GetActiveFaviconImage() override;
   const GURL GetActiveFaviconURL() override;
   bool GetActiveFaviconValidity() override;
   const GURL GetActiveURL() override;
-  void SetActiveFaviconImage(gfx::Image image) override;
-  void SetActiveFaviconURL(GURL url) override;
-  void SetActiveFaviconValidity(bool validity) override;
+  void OnFaviconAvailable(const gfx::Image& image,
+                          const GURL& url,
+                          bool update_active_favicon) override;
 
   // Favicon download callback.
   void DidDownloadFavicon(
       int id,
       int http_status_code,
       const GURL& image_url,
       const std::vector<SkBitmap>& bitmaps,
       const std::vector<gfx::Size>& original_bitmap_sizes);
 
  private:
   explicit FaviconTabHelper(content::WebContents* web_contents);
   friend class content::WebContentsUserData<FaviconTabHelper>;
 
   // content::WebContentsObserver overrides.
   void DidStartNavigationToPendingEntry(
       const GURL& url,
       content::NavigationController::ReloadType reload_type) override;
   void DidNavigateMainFrame(
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) override;
 
+  // Sets whether the page's favicon is valid (if false, the default favicon is
+  // being used). Requires GetActiveURL() to be valid.
+  void SetActiveFaviconValidity(bool validity);
+
+  // Sets the URL of the favicon's bitmap.
+  void SetActiveFaviconURL(GURL url);
+
+  // Sets the bitmap of the current page's favicon.
+  void SetActiveFaviconImage(gfx::Image image);
+
   // Helper method that returns the active navigation entry's favicon.
   content::FaviconStatus& GetFaviconStatus();
 
   Profile* profile_;
 
   FaviconClient* client_;
 
   std::vector<content::FaviconURL> favicon_urls_;
 
   scoped_ptr<FaviconHandler> favicon_handler_;
 
   // Handles downloading touchicons. It is NULL if
   // browser_defaults::kEnableTouchIcon is false.
   scoped_ptr<FaviconHandler> touch_icon_handler_;
 
+  ObserverList<Observer> observer_list_;
+
   DISALLOW_COPY_AND_ASSIGN(FaviconTabHelper);
 };
 
 #endif  // CHROME_BROWSER_FAVICON_FAVICON_TAB_HELPER_H_