Download large icon if available when creating secondary tiles on Windows 8.

chrome/browser/ui/metro_pin_tab_helper_win.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_METRO_PIN_TAB_HELPER_WIN_H_
 #define CHROME_BROWSER_UI_METRO_PIN_TAB_HELPER_WIN_H_
 
+#include <vector>
+
+#include "chrome/common/favicon_url.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/image/image_skia.h"
 
 // Per-tab class to help manage metro pinning.
 class MetroPinTabHelper
     : public content::WebContentsObserver,
       public content::WebContentsUserData<MetroPinTabHelper> {
  public:
   virtual ~MetroPinTabHelper();
 
   bool is_pinned() const { return is_pinned_; }
 
   void TogglePinnedToStartScreen();
 
   // content::WebContentsObserver overrides:
   virtual void DidNavigateMainFrame(
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE;
 
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
  private:
-  // The TaskRunner handles running tasks for this helper on the FILE thread.
-  class TaskRunner;
+  // The FaviconDownloader class handles downloading the favicons when a page
+  // is being pinned. After it has downloaded any available favicons it will
+  // continue on with the page pinning action.
+  class FaviconDownloader;
 
   explicit MetroPinTabHelper(content::WebContents* tab_contents);
   friend class content::WebContentsUserData<MetroPinTabHelper>;
 
+  // Message Handlers.
+  void OnUpdateFaviconURL(int32 page_id,
+                          const std::vector<FaviconURL>& candidates);
+  void OnDidDownloadFavicon(int id,
+                            const GURL& image_url,
+                            bool errored,
+                            int requested_size,
+                            const std::vector<SkBitmap>& bitmaps);
+
   // Queries the metro driver about the pinned state of the current URL.
   void UpdatePinnedStateForCurrentURL();
 
   void UnPinPageFromStartScreen();
 
+  // Called by the |favicon_downloader_| when it has finished.
+  void FaviconDownloaderFinished();
+
   // Whether the current URL is pinned to the metro start screen.
   bool is_pinned_;
 
-  // The task runner for the helper, which runs things for it on the FILE
-  // thread.
-  scoped_refptr<TaskRunner> task_runner_;
+  // Candidate Favicon URLs for the current page.
+  std::vector<FaviconURL> favicon_url_candidates_;
+
+  // The currently active FaviconDownloader, if there is one.
+  scoped_ptr<FaviconDownloader> favicon_downloader_;
 
   DISALLOW_COPY_AND_ASSIGN(MetroPinTabHelper);
 };
 
 #endif  // CHROME_BROWSER_UI_METRO_PIN_TAB_HELPER_WIN_H_