Convert //chrome/browser/sync_file_system from scoped_ptr to std::unique_ptr

chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc

 // 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.
 
 #include "chrome/browser/sync_file_system/local/local_file_sync_context.h"
 
 #include <stdint.h>
 #include <utility>
 #include <vector>
 
@@ skipping 330 matching lines @@
     EXPECT_TRUE(changes.list().back().IsFile());
     EXPECT_TRUE(changes.list().back().IsAddOrUpdate());
 
     sync_context_->ShutdownOnUIThread();
     sync_context_ = nullptr;
 
     file_system.TearDown();
   }
 
   base::ScopedTempDir dir_;
-  scoped_ptr<leveldb::Env> in_memory_env_;
+  std::unique_ptr<leveldb::Env> in_memory_env_;
 
   // These need to remain until the very end.
   content::TestBrowserThreadBundle thread_bundle_;
 
   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
 
   scoped_refptr<LocalFileSyncContext> sync_context_;
 
@@ skipping 591 matching lines @@
 
   // Make sure kDir and kFile are created by ApplyRemoteChange.
   EXPECT_EQ(base::File::FILE_OK, file_system.FileExists(kFile));
   EXPECT_EQ(base::File::FILE_OK, file_system.DirectoryExists(kDir));
 
   sync_context_->ShutdownOnUIThread();
   file_system.TearDown();
 }
 
 }  // namespace sync_file_system