[Sync] Fix Session's handling of windows.

chrome/browser/sessions/session_restore.h

 // Copyright (c) 2011 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_RESTORE_H_
 #define CHROME_BROWSER_SESSIONS_SESSION_RESTORE_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 29 matching lines @@
   // If |urls_to_open| is non-empty, a tab is added for each of the URLs.
   static Browser* RestoreSession(Profile* profile,
                                  Browser* browser,
                                  uint32 behavior,
                                  const std::vector<GURL>& urls_to_open);
 
   // Specifically used in the restoration of a foreign session.  This method
   // restores the given session windows to a browser.
   static void RestoreForeignSessionWindows(
       Profile* profile,
-      std::vector<SessionWindow*>::const_iterator begin,
-      std::vector<SessionWindow*>::const_iterator end);
+      std::vector<const SessionWindow*>::const_iterator begin,
+      std::vector<const SessionWindow*>::const_iterator end);
 
   // Specifically used in the restoration of a foreign session.  This method
   // restores the given session tab to a browser.
   static void RestoreForeignSessionTab(Profile* profile,
                                        const SessionTab& tab);
 
   // Returns true if we're in the process of restoring.
   static bool IsRestoring();
 
   // The max number of non-selected tabs SessionRestore loads when restoring
   // a session. A value of 0 indicates all tabs are loaded at once.
   static size_t num_tabs_to_load_;
 
  private:
   SessionRestore();
 
   DISALLOW_COPY_AND_ASSIGN(SessionRestore);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_SESSION_RESTORE_H_