Move chrome-specific SerializedNavigation code to chrome/.

components/sessions/content/content_serialized_navigation_driver.h

 // Copyright 2014 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_CONTENT_CONTENT_SERIALIZED_NAVIGATION_DRIVER_H_
 #define COMPONENTS_SESSIONS_CONTENT_CONTENT_SERIALIZED_NAVIGATION_DRIVER_H_
 
-#include "components/sessions/core/serialized_navigation_driver.h"
-
 #include <map>
 #include <memory>
 #include <string>
 
 #include "base/macros.h"
 #include "components/sessions/content/extended_info_handler.h"
+#include "components/sessions/core/serialized_navigation_driver.h"
 #include "components/sessions/core/sessions_export.h"
 
 namespace base {
 template <typename T> struct DefaultSingletonTraits;
 }
 
 namespace sessions {
 
 // Provides an implementation of SerializedNavigationDriver that is backed by
 // content classes.
 class SESSIONS_EXPORT ContentSerializedNavigationDriver
     : public SerializedNavigationDriver {
  public:
   ~ContentSerializedNavigationDriver() override;
 
   // Returns the singleton ContentSerializedNavigationDriver.  Almost all
   // callers should use SerializedNavigationDriver::Get() instead.
   static ContentSerializedNavigationDriver* GetInstance();
 
+  // Allows an embedder to override the instance returned by GetInstance().
+  static void SetInstance(ContentSerializedNavigationDriver* instance);
+
   // SerializedNavigationDriver implementation.
   int GetDefaultReferrerPolicy() const override;
   bool MapReferrerPolicyToOldValues(int referrer_policy,
                                     int* mapped_referrer_policy) const override;
   bool MapReferrerPolicyToNewValues(int referrer_policy,
                                     int* mapped_referrer_policy) const override;
   std::string GetSanitizedPageStateForPickle(
       const SerializedNavigationEntry* navigation) const override;
   void Sanitize(SerializedNavigationEntry* navigation) const override;
   std::string StripReferrerFromPageState(
       const std::string& page_state) const override;
 
   // Registers a handler that is used to read and write the extended
   // info stored in SerializedNavigationEntry. As part of serialization |key|
   // is written to disk, as such once a handler is registered it should always
   // be registered to the same key.
   void RegisterExtendedInfoHandler(
       const std::string& key,
       std::unique_ptr<ExtendedInfoHandler> handler);
 
   using ExtendedInfoHandlerMap =
       std::map<std::string, std::unique_ptr<ExtendedInfoHandler>>;
 
   // Returns all the registered handlers to deal with the extended info.
   const ExtendedInfoHandlerMap& GetAllExtendedInfoHandlers() const;
 
+ protected:
+  ContentSerializedNavigationDriver();
+
  private:
   friend struct base::DefaultSingletonTraits<ContentSerializedNavigationDriver>;
   friend class ContentSerializedNavigationBuilderTest;
 
-  ContentSerializedNavigationDriver();
-
   ExtendedInfoHandlerMap extended_info_handler_map_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentSerializedNavigationDriver);
 };
 
 }  // namespace sessions
 
 #endif  // COMPONENTS_SESSIONS_CONTENT_CONTENT_SERIALIZED_NAVIGATION_DRIVER_H_