Clean ReadingListModel.

components/reading_list/ios/reading_list_model_impl.h

Index: components/reading_list/ios/reading_list_model_impl.h
diff --git a/components/reading_list/ios/reading_list_model_impl.h b/components/reading_list/ios/reading_list_model_impl.h
index 1ff505637a4b2f4c7e5e68221b28d37d3e4ef623..c49d713d754fcbf3761be435586d109eefc72d14 100644
--- a/components/reading_list/ios/reading_list_model_impl.h
+++ b/components/reading_list/ios/reading_list_model_impl.h
@@ -46,7 +46,6 @@ class ReadingListModelImpl : public ReadingListModel,
 
   size_t size() const override;
   size_t unread_size() const override;
-  size_t read_size() const override;
 
   bool HasUnseenEntries() const override;
   void ResetUnseenEntries() override;
@@ -54,10 +53,6 @@ class ReadingListModelImpl : public ReadingListModel,
   const std::vector<GURL> Keys() const override;
 
   const ReadingListEntry* GetEntryByURL(const GURL& gurl) const override;
-  const ReadingListEntry& GetUnreadEntryAtIndex(size_t index) const override;
-  const ReadingListEntry& GetReadEntryAtIndex(size_t index) const override;
-  void MarkReadByURL(const GURL& url) override;
-  void MarkUnreadByURL(const GURL& url) override;
 
   void RemoveEntryByURL(const GURL& url) override;
 
@@ -121,17 +116,6 @@ class ReadingListModelImpl : public ReadingListModel,
   size_t unread_entry_count_;
   size_t read_entry_count_;
 
-  // TODO(crbug.com/664924): Remove temporary cache and move it to
-  // ReadingListViewController.
-  struct Cache {
-    Cache();
-    ~Cache();
-    std::vector<GURL> read_entries;
-    std::vector<GURL> unread_entries;
-    bool dirty;
-  };
-  std::unique_ptr<struct Cache> cache_;
-
   std::unique_ptr<ReadingListModelStorage> storage_layer_;
   PrefService* pref_service_;
   bool has_unseen_;