Switch SupportsUserData uses to use unique_ptr.

components/history/core/browser/history_backend.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 COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 435 matching lines @@
   // things go better then. Continue running but without reading or storing any
   // state into the HistoryBackend databases. Close all of the databases managed
   // HistoryBackend as there are no provisions for accessing the other databases
   // managed by HistoryBackend when the history database cannot be accessed.
   void KillHistoryDatabase();
 
   // SupportsUserData ----------------------------------------------------------
 
   // The user data allows the clients to associate data with this object.
   // Multiple user data values can be stored under different keys.
-  // This object will TAKE OWNERSHIP of the given data pointer, and will
-  // delete the object if it is changed or the object is destroyed.
   base::SupportsUserData::Data* GetUserData(const void* key) const;
-  void SetUserData(const void* key, base::SupportsUserData::Data* data);
+  void SetUserData(const void* key,
+                   std::unique_ptr<base::SupportsUserData::Data> data);
 
   // Testing -------------------------------------------------------------------
 
   // Sets the task to run and the message loop to run it on when this object
   // is destroyed. See HistoryService::SetOnBackendDestroyTask for a more
   // complete description.
   void SetOnBackendDestroyTask(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner,
       const base::Closure& task);
 
@@ skipping 450 matching lines @@
   // it unregisters itself as observer during destruction.
   std::unique_ptr<TypedUrlSyncableService> typed_url_syncable_service_;
   std::unique_ptr<TypedURLSyncBridge> typed_url_sync_bridge_;
 
   DISALLOW_COPY_AND_ASSIGN(HistoryBackend);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_