Standardize usage of virtual/override/final in chrome/browser/sync_file_system/

chrome/browser/sync_file_system/local/local_file_sync_service_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 <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
@@ skipping 130 matching lines @@
 
   virtual void TearDown() override {
     local_service_->Shutdown();
     file_system_->TearDown();
     RevokeSyncableFileSystem();
     content::RunAllPendingInMessageLoop(BrowserThread::FILE);
     content::RunAllPendingInMessageLoop(BrowserThread::IO);
   }
 
   // LocalChangeObserver overrides.
-  virtual void OnLocalChangeAvailable(int64 num_changes) override {
+  void OnLocalChangeAvailable(int64 num_changes) override {
     num_changes_ = num_changes;
   }
 
   void PrepareForProcessRemoteChange(
       const FileSystemURL& url,
       const tracked_objects::Location& where,
       SyncStatusCode expected_status,
       const SyncFileMetadata& expected_metadata) {
     base::RunLoop run_loop;
     local_service_->PrepareForProcessRemoteChange(
@@ skipping 564 matching lines @@
   all_origins.insert(kOrigin2);
   all_origins.insert(kOrigin3);
   while (!all_origins.empty()) {
     ASSERT_TRUE(NextOriginToProcess(&origin));
     ASSERT_TRUE(ContainsKey(all_origins, origin));
     all_origins.erase(origin);
   }
 }
 
 }  // namespace sync_file_system