Created SerializedUserDataManager.

ios/web/public/navigation_manager.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 IOS_WEB_PUBLIC_NAVIGATION_MANAGER_H_
 #define IOS_WEB_PUBLIC_NAVIGATION_MANAGER_H_
 
+#include "base/supports_user_data.h"
 #include "ios/web/public/browser_url_rewriter.h"
 
 namespace web {
 
 class BrowserState;
 class NavigationItem;
 class WebState;
 
 // A NavigationManager maintains the back-forward list for a WebState and
 // manages all navigation within that list.
 //
 // Each NavigationManager belongs to one WebState; each WebState has
 // exactly one NavigationManager.
-class NavigationManager {
+class NavigationManager : public base::SupportsUserData {

[Eugene But (OOO till 7-30), 2015/09/24 17:05:07]

Is there any specific reason why NavigationManager is a base::SupportsUserData
subclass? Can you make NavigationManagerImpl support user data?

[kkhorimoto, 2015/09/24 21:24:29]

I initially did this because of the style guide's rules on multiple inheritance
in C++ (SupportsUserData is not a pure interface).  However, I've updated the
implementation to simply use the web state's user data.

  public:
-  virtual ~NavigationManager() {}
+  ~NavigationManager() override {}
 
   // Gets the BrowserState associated with this NavigationManager. Can never
   // return null.
   virtual BrowserState* GetBrowserState() const = 0;
 
   // Gets the WebState associated with this NavigationManager.
   virtual WebState* GetWebState() const = 0;
 
   // Returns the NavigationItem that should be used when displaying info about
   // the current entry to the user. It ignores certain pending entries, to
@@ skipping 36 matching lines @@
   virtual int GetCurrentEntryIndex() const = 0;
 
   // Returns the index of the pending item or -1 if the pending item
   // corresponds to a new navigation.
   virtual int GetPendingItemIndex() const = 0;
 };
 
 }  // namespace web
 
 #endif  // IOS_WEB_PUBLIC_NAVIGATION_MANAGER_H_