Persist sessionStorage on disk.

chrome/browser/sessions/session_types.h

 // Copyright (c) 2012 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 CHROME_BROWSER_SESSIONS_SESSION_TYPES_H_
 #define CHROME_BROWSER_SESSIONS_SESSION_TYPES_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 154 matching lines @@
 
   // If non-empty, this string is used as the user agent whenever the tab's
   // NavigationEntries need it overridden.
   std::string user_agent_override;
 
   // Timestamp for when this tab was last modified.
   base::Time timestamp;
 
   std::vector<TabNavigation> navigations;
 
+  // For reassociating sessionStorage.
+  std::string session_storage_persistent_id;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(SessionTab);
 };
 
 // SessionWindow -------------------------------------------------------------
 
 // Describes a saved window.
 struct SessionWindow {
   SessionWindow();
   ~SessionWindow();
@@ skipping 33 matching lines @@
   // Is the window maximized, minimized, or normal?
   ui::WindowShowState show_state;
 
   std::string app_name;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SessionWindow);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_SESSION_TYPES_H_