Introduce ManifestUpgradeDetector for WebAPK to detect web manifest changes.

chrome/browser/android/webapps/add_to_homescreen_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_WEBAPPS_ADD_TO_HOMESCREEN_DATA_FETCHER_H_
 #define CHROME_BROWSER_ANDROID_WEBAPPS_ADD_TO_HOMESCREEN_DATA_FETCHER_H_
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/task/cancelable_task_tracker.h"
@@ skipping 20 matching lines @@
 // Because of the various asynchronous calls made by this class, it is
 // refcounted to prevent the class from being prematurely deleted.  If the
 // pointer to the ShortcutHelper becomes invalid, the pipeline should kill
 // itself.
 class AddToHomescreenDataFetcher
     : public base::RefCounted<AddToHomescreenDataFetcher>,
       public content::WebContentsObserver {
  public:
   class Observer {
    public:
+    virtual void OnDidHasManifest(bool has_manifest) = 0;
+
     // Called when the title of the page is available.
     virtual void OnUserTitleAvailable(const base::string16& title) = 0;
 
     // Converts the icon into one that can be used on the Android Home screen.
     // |is_generated| is an out-param that indicates whether the icon was
     // generated by Chrome.
     virtual SkBitmap FinalizeLauncherIcon(const SkBitmap& icon,
                                           const GURL& url,
                                           bool* is_generated) = 0;
 
     // Called when all the data needed to create a shortcut is available.
     virtual void OnDataAvailable(const ShortcutInfo& info,
-                                 const SkBitmap& icon) = 0;
+                                 const SkBitmap& icon,
+                                 const std::vector<std::string>& icon_urls) = 0;
   };
 
   // Initialize the fetcher by requesting the information about the page to the
   // renderer process. The initialization is asynchronous and
   // OnDidGetWebApplicationInfo is expected to be called when finished.
   AddToHomescreenDataFetcher(content::WebContents* web_contents,
                              int ideal_icon_size_in_dp,
                              int minimum_icon_size_in_dp,
                              int ideal_splash_image_size_in_dp,
                              int minimum_splash_image_size_in_dp,
+                             bool stop_fetch_when_no_manifest,
                              Observer* observer);
 
+  // Replaces the WebContents that is being observed.
+  void ReplaceWebContents(content::WebContents* web_contents);
+
   // Returns a callback which fetches the splash screen image to be stored for
   // the webapp with the specified |id|.
   base::Closure FetchSplashScreenImageCallback(const std::string& id);
 
   // IPC message received when the initialization is finished.
   void OnDidGetWebApplicationInfo(const WebApplicationInfo& web_app_info);
 
+  void OnDidHasManifest(bool has_manifest);
+
   // Called when the Manifest has been parsed, or if no Manifest was found.
   void OnDidGetManifest(const GURL& manifest_url,
                         const content::Manifest& manifest);
 
   // Accessors, etc.
   void set_weak_observer(Observer* observer) { weak_observer_ = observer; }
   bool is_ready() { return is_ready_; }
   ShortcutInfo& shortcut_info() { return shortcut_info_; }
   const SkBitmap& shortcut_icon() { return shortcut_icon_; }
 
@@ skipping 26 matching lines @@
 
   Observer* weak_observer_;
 
   bool is_waiting_for_web_application_info_;
   bool is_icon_saved_;
   bool is_ready_;
   base::Timer icon_timeout_timer_;
   ShortcutInfo shortcut_info_;
   GURL splash_screen_url_;
 
+  std::vector<std::string> icon_urls_;
   // The icon must only be set on the UI thread for thread safety.
   SkBitmap shortcut_icon_;
   base::CancelableTaskTracker favicon_task_tracker_;
 
   const int ideal_icon_size_in_dp_;
   const int minimum_icon_size_in_dp_;
   const int ideal_splash_image_size_in_dp_;
   const int minimum_splash_image_size_in_dp_;
 
+  const bool stop_fetch_when_no_manifest_;
+
   friend class base::RefCounted<AddToHomescreenDataFetcher>;
   DISALLOW_COPY_AND_ASSIGN(AddToHomescreenDataFetcher);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_WEBAPPS_ADD_TO_HOMESCREEN_DATA_FETCHER_H_