Store distilled URL during distillation in Reading List on iOS

ios/chrome/browser/reading_list/reading_list_distiller_page.h

 // Copyright 2016 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 IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DISTILLER_PAGE_H_
 #define IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DISTILLER_PAGE_H_
 
 #include <memory>
 #include <string>
 
 #include "base/memory/weak_ptr.h"
 #include "components/dom_distiller/ios/distiller_page_ios.h"
 #include "url/gurl.h"
 
 namespace web {
 class BrowserState;
 }
 
 namespace reading_list {
 
 class FaviconWebStateDispatcher;
 
 // An DistillerPageIOS that will retain WebState to allow favicon download and
 // and add a 2 seconds delay between loading and distillation.
 class ReadingListDistillerPage : public dom_distiller::DistillerPageIOS {
  public:
+  typedef base::Callback<void(const GURL&, const GURL&)> RedirectionCallback;
+
   explicit ReadingListDistillerPage(
       web::BrowserState* browser_state,
       FaviconWebStateDispatcher* web_state_dispatcher);
   ~ReadingListDistillerPage() override;
 
+  // Sets a callback that will be called just before distillation happen with
+  // the URL of the page that will effectively be distilled.
+  void SetRedirectionCallback(RedirectionCallback redirection_callback);
+
  protected:
   void DistillPageImpl(const GURL& url, const std::string& script) override;
   void OnDistillationDone(const GURL& page_url,
                           const base::Value* value) override;
   void OnLoadURLDone(
       web::PageLoadCompletionStatus load_completion_status) override;
 
  private:
   // Returns wether there is the loading has no error and if the distillation
   // can continue.
   bool IsLoadingSuccess(web::PageLoadCompletionStatus load_completion_status);
   // Work around the fact that articles opened from Google Search page and
   // Google News are presented in an iframe. This method detects if the current
   // page is a Google AMP and navigate to the iframe in that case.
   // Returns whether the current page is a Google AMP page.
   // IsGoogleCachedAMPPage will determine if the current page is a Google AMP
   // page.
   bool IsGoogleCachedAMPPage();
   // HandleGoogleCachedAMPPage will navigate to the iframe containing the actual
   // article page.
   void HandleGoogleCachedAMPPage();
   // Handles the JavaScript response. If the URL of the iframe is returned,
   // triggers a navigation to it. Stop distillation of the page there as the new
   // load will trigger a new distillation.
-  bool HandleGoogleCachedAMPPageJavaScriptResult(id result, NSError* error);
+  bool HandleGoogleCachedAMPPageJavaScriptResult(id result, id error);
 
   // Waits a delay then calls DelayedOnLoadURLDone.
   void WaitForPageLoadCompletion();
 
   // Continues distillation by calling superclass |OnLoadURLDone|.
   void DelayedOnLoadURLDone();
 
+  RedirectionCallback redirection_callback_;
+  GURL original_url_;
+
   FaviconWebStateDispatcher* web_state_dispatcher_;
   base::WeakPtrFactory<ReadingListDistillerPage> weak_ptr_factory_;
 };
 
 }  // namespace reading_list
 
 #endif  // IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DISTILLER_PAGE_H_