Introduce timeout for downloading a favicon for adding to Home screen

chrome/browser/android/shortcut_data_fetcher.h

 // Copyright 2015 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_ANDROID_SHORTCUT_DATA_FETCHER_H_
 #define CHROME_BROWSER_ANDROID_SHORTCUT_DATA_FETCHER_H_
 
 #include "base/basictypes.h"
 #include "base/task/cancelable_task_tracker.h"
+#include "base/timer/timer.h"
 #include "chrome/browser/android/shortcut_info.h"
 #include "chrome/common/web_application_info.h"
 #include "components/favicon_base/favicon_types.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/common/manifest.h"
 
 namespace content {
 class WebContents;
 }  // namespace content
 
@@ skipping 62 matching lines @@
 
   // Callback run after an attempt to download manifest icon has been made.  May
   // kick off the download of a favicon if it failed.
   void OnManifestIconFetched(int id,
                              int http_status_code,
                              const GURL& url,
                              const std::vector<SkBitmap>& bitmaps,
                              const std::vector<gfx::Size>& sizes);
 
   // Notifies the observer that the shortcut data is all available.
-  void NotifyObserver();
+  void NotifyObserver(const SkBitmap& icon);
 
   Observer* weak_observer_;
 
   bool is_waiting_for_web_application_info_;
   bool is_ready_;
+  base::Timer icon_timeout_timer_;
   ShortcutInfo shortcut_info_;
+
+  // The icon must only be set on the UI thread for thread safety.
   SkBitmap shortcut_icon_;
-  base::CancelableTaskTracker cancelable_task_tracker_;
+  base::CancelableTaskTracker favicon_task_tracker_;
 
   const int preferred_icon_size_in_px_;
   static const int kPreferredIconSizeInDp;
 
   friend class base::RefCounted<ShortcutDataFetcher>;
   DISALLOW_COPY_AND_ASSIGN(ShortcutDataFetcher);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_SHORTCUT_DATA_FETCHER_H_