Update {virtual,override} to follow C++11 style in sync.

sync/internal_api/sync_rollback_manager_unittest.cc

 // 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.
 
 #include "sync/internal_api/sync_rollback_manager.h"
 
 #include "base/files/scoped_temp_dir.h"
 #include "base/run_loop.h"
 #include "sync/internal_api/public/read_node.h"
 #include "sync/internal_api/public/read_transaction.h"
@@ skipping 50 matching lines @@
     }
     EXPECT_TRUE(expected_deletes_ == deleted);
   }
 
   std::set<int64> expected_deletes_;
 };
 
 class SyncRollbackManagerTest : public testing::Test,
                                 public SyncManager::Observer {
  protected:
-  virtual void SetUp() override {
+  void SetUp() override {
     CHECK(temp_dir_.CreateUniqueTempDir());
 
     worker_ = new FakeModelWorker(GROUP_UI);
   }
 
   MOCK_METHOD1(OnSyncCycleCompleted,
                void(const sessions::SyncSessionSnapshot&));
   MOCK_METHOD1(OnConnectionStatusChange, void(ConnectionStatus));
   MOCK_METHOD4(OnInitializationComplete,
                void(const WeakHandle<JsBackend>&,
@@ skipping 177 matching lines @@
   // Test graceful shutdown on initialization failure.
   scoped_ptr<SyncRollbackManager> rollback_manager(
       new SyncRollbackManager);
   InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES), NULL,
               InternalComponentsFactory::STORAGE_ON_DISK);
 }
 
 }  // anonymous namespace
 
 }  // namespace syncer