Store distilled URL during distillation in Reading List on iOS

ios/chrome/browser/reading_list/reading_list_distiller_page.h

Index: ios/chrome/browser/reading_list/reading_list_distiller_page.h
diff --git a/ios/chrome/browser/reading_list/reading_list_distiller_page.h b/ios/chrome/browser/reading_list/reading_list_distiller_page.h
index 891de56b75bacf33df1669a332442005352dad33..8ebbfc80d42a8075b9b29628af6be86ddd660ff1 100644
--- a/ios/chrome/browser/reading_list/reading_list_distiller_page.h
+++ b/ios/chrome/browser/reading_list/reading_list_distiller_page.h
@@ -24,11 +24,17 @@ class FaviconWebStateDispatcher;
 // 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,
@@ -53,7 +59,7 @@ class ReadingListDistillerPage : public dom_distiller::DistillerPageIOS {
   // 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();
@@ -61,6 +67,9 @@ class ReadingListDistillerPage : public dom_distiller::DistillerPageIOS {
   // Continues distillation by calling superclass |OnLoadURLDone|.
   void DelayedOnLoadURLDone();
 
+  RedirectionCallback redirection_callback_;
+  GURL original_url_;
+
   FaviconWebStateDispatcher* web_state_dispatcher_;
   base::WeakPtrFactory<ReadingListDistillerPage> weak_ptr_factory_;
 };