Standardize usage of virtual/override/final specifiers in sync/.

sync/syncable/directory_backing_store_unittest.cc

 // Copyright 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.
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 14 matching lines @@
 #include "sync/util/time.h"
 #include "testing/gtest/include/gtest/gtest-param-test.h"
 
 namespace syncer {
 namespace syncable {
 
 SYNC_EXPORT_PRIVATE extern const int32 kCurrentDBVersion;
 
 class MigrationTest : public testing::TestWithParam<int> {
  public:
-  virtual void SetUp() {
-    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
-  }
+  void SetUp() override { ASSERT_TRUE(temp_dir_.CreateUniqueTempDir()); }
 
  protected:
   std::string GetUsername() {
     return "nick@chromium.org";
   }
 
   base::FilePath GetDatabasePath() {
     return temp_dir_.path().Append(Directory::kSyncDatabaseFilename);
   }
 
@@ skipping 3902 matching lines @@
   const std::string& guid2 = TestDirectoryBackingStore::GenerateCacheGUID();
   EXPECT_EQ(24U, guid1.size());
   EXPECT_EQ(24U, guid2.size());
   // In theory this test can fail, but it won't before the universe
   // dies of heat death.
   EXPECT_NE(guid1, guid2);
 }
 
 }  // namespace syncable
 }  // namespace syncer