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..7079caf38ae41fb5fe141243a66405ead77a413f 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
@@ -12,6 +12,10 @@
 
 class ReadingListModel;
 
+namespace web {
+class NavigationItem;
+}
+
 // Observes the loading of pages coming from the reading list, determines
 // whether loading an offline version of the page is needed, and actually
 // trigger the loading of the offline page (if possible).
@@ -45,8 +49,14 @@ 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();
+
+  // The item of the current navigation.

[Eugene But (OOO till 7-30), 2016/12/19 17:52:32]

The logic behind this method is quite complicated and requires more comments.
F.e. The result of this this should not be used in the Omnibox because Pending
Item can only be displayed if it was not renderer initiated.

[Olivier, 2016/12/19 18:26:38]

Removed as GetVisibleItem seems to be what I need.

+  web::NavigationItem* CurrentItem();
+
   // WebContentsObserver implementation.
-  void DidStopLoading() override;
+  void DidStartLoading() override;
   void PageLoaded(
       web::PageLoadCompletionStatus load_completion_status) override;
   void WebStateDestroyed() override;