Reload offline version on load failure

ios/chrome/browser/reading_list/reading_list_web_state_observer.h

Index: ios/chrome/browser/reading_list/reading_list_web_state_observer.h
diff --git a/ios/chrome/browser/reading_list/reading_list_web_state_observer.h b/ios/chrome/browser/reading_list/reading_list_web_state_observer.h
index 47fcfb6f9aa4c0075e442c5ac0b852bb6dfc376f..804537b762e92c4e6d195106058d2cadd666a52a 100644
--- a/ios/chrome/browser/reading_list/reading_list_web_state_observer.h
+++ b/ios/chrome/browser/reading_list/reading_list_web_state_observer.h
@@ -45,8 +45,11 @@ class ReadingListWebStateObserver : public web::WebStateObserver {
   // The WebState will still be observed, but no action will be done on events.
   void StopCheckingProgress();
 
+  // Load the distilled version of the URL in place of the current page.
+  void LoadReadingListDistilled();
+
   // WebContentsObserver implementation.
-  void DidStopLoading() override;
+  void DidStartLoading() override;
   void PageLoaded(
       web::PageLoadCompletionStatus load_completion_status) override;
   void WebStateDestroyed() override;