Persist offline page info in a navigation entry if needed

components/sessions/core/serialized_navigation_entry.h

 // Copyright 2013 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 COMPONENTS_SESSIONS_CORE_SERIALIZED_NAVIGATION_ENTRY_H_
 #define COMPONENTS_SESSIONS_CORE_SERIALIZED_NAVIGATION_ENTRY_H_
 
 #include <stdint.h>
 
+#include <map>
 #include <memory>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "components/sessions/core/sessions_export.h"
 #include "ui/base/page_transition_types.h"
 #include "url/gurl.h"
@@ skipping 96 matching lines @@
 
   std::set<std::string> content_pack_categories() const {
     return content_pack_categories_;
   }
   void set_content_pack_categories(
       const std::set<std::string>& content_pack_categories) {
     content_pack_categories_ = content_pack_categories;
   }
   const std::vector<GURL>& redirect_chain() const { return redirect_chain_; }
 
+#if !defined(OS_IOS)

[sky, 2016/09/29 03:08:20]

I'm nervous about making this non-ios specific. Seems easier to write it
everywhere. On ios it'll be empty, but that's ok, right?

[jianli, 2016/09/29 22:02:29]

Yes. Removed #if.

+  const std::map<std::string, std::string>& extended_info_map() const {
+    return extended_info_map_;
+  }
+#endif  // !defined(OS_IOS)
+
  private:
   friend class ContentSerializedNavigationBuilder;
   friend class ContentSerializedNavigationDriver;
   friend class SerializedNavigationEntryTestHelper;
   friend class IOSSerializedNavigationBuilder;
   friend class IOSSerializedNavigationDriver;
 
   // Index in the NavigationController.
   int index_;
 
@@ skipping 13 matching lines @@
   base::string16 search_terms_;
   GURL favicon_url_;
   int http_status_code_;
   bool is_restored_;    // Not persisted.
   std::vector<GURL> redirect_chain_;  // Not persisted.
 
   // Additional information.
   BlockedState blocked_state_;
   PasswordState password_state_;
   std::set<std::string> content_pack_categories_;
+
+#if !defined(OS_IOS)
+  // The map that tracks all the extended info that need to be persisted, but

[sky, 2016/09/29 03:08:19]

How about: provides storage for arbitrary key/value pairs used by features. This
data is not synced.

+  // would want to avoid the core session restore to know about the details.
+  // The consumer should implement the ExtendedInfoHandler interface and calls
+  // SerializedNavigationDriver::RegisterExtendedInfoHandler to register it.
+  // Note that all the map data are not synced since the only one added now does
+  // not need it.
+  std::map<std::string, std::string> extended_info_map_;
+#endif  // !defined(OS_IOS)
 };
 
 }  // namespace sessions
 
 #endif  // COMPONENTS_SESSIONS_CORE_SERIALIZED_NAVIGATION_ENTRY_H_