[Sync] Ensure referrer is recorded regardless of policy conversion

components/sessions/content/content_serialized_navigation_driver.h

Index: components/sessions/content/content_serialized_navigation_driver.h
diff --git a/components/sessions/content/content_serialized_navigation_driver.h b/components/sessions/content/content_serialized_navigation_driver.h
index ec732a707661378a6e30f9ce3bff6bcbbe964fa4..82a9b81aa50c18378e0935f7ede5c03872c54b43 100644
--- a/components/sessions/content/content_serialized_navigation_driver.h
+++ b/components/sessions/content/content_serialized_navigation_driver.h
@@ -36,10 +36,6 @@ class SESSIONS_EXPORT ContentSerializedNavigationDriver
 
   // 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;