Standardize usage of virtual/override/final in sync/

sync/api/fake_sync_change_processor.h

 // 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.
 
 #ifndef SYNC_API_FAKE_SYNC_CHANGE_PROCESSOR_H_
 #define SYNC_API_FAKE_SYNC_CHANGE_PROCESSOR_H_
 
 #include "sync/api/sync_change_processor.h"
 
 namespace syncer {
 
 class FakeSyncChangeProcessor : public SyncChangeProcessor {
  public:
   FakeSyncChangeProcessor();
-  virtual ~FakeSyncChangeProcessor();
+  ~FakeSyncChangeProcessor() override;
 
   // SyncChangeProcessor implementation.
   //
   // ProcessSyncChanges will accumulate changes in changes() until they are
   // cleared.
-  virtual syncer::SyncError ProcessSyncChanges(
+  syncer::SyncError ProcessSyncChanges(
       const tracked_objects::Location& from_here,
       const syncer::SyncChangeList& change_list) override;
 
   // SyncChangeProcessor implementation.
   //
   // Returns data().
-  virtual syncer::SyncDataList GetAllSyncData(syncer::ModelType type)
-      const override;
+  syncer::SyncDataList GetAllSyncData(syncer::ModelType type) const override;
 
   // SyncChangeProcessor implementation.
   //
   // Updates context().
-  virtual syncer::SyncError UpdateDataTypeContext(
-      ModelType type,
-      ContextRefreshStatus refresh_status,
-      const std::string& context) override;
+  syncer::SyncError UpdateDataTypeContext(ModelType type,
+                                          ContextRefreshStatus refresh_status,
+                                          const std::string& context) override;
 
   virtual const syncer::SyncChangeList& changes() const;
   virtual syncer::SyncChangeList& changes();
 
   virtual const syncer::SyncDataList& data() const;
   virtual syncer::SyncDataList& data();
 
   virtual const std::string& context() const;
   virtual std::string& context();
 
  private:
   syncer::SyncChangeList changes_;
   syncer::SyncDataList data_;
   std::string context_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeSyncChangeProcessor);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_API_FAKE_SYNC_CHANGE_PROCESSOR_H_