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

sync/internal_api/attachments/fake_attachment_uploader_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/public/attachments/fake_attachment_uploader.h"
 
 #include "base/bind.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/message_loop/message_loop.h"
 #include "sync/api/attachments/attachment.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace syncer {
 
 namespace {
 
 const char kAttachmentData[] = "some data";
 
 }  // namespace
 
 class FakeAttachmentUploaderTest : public testing::Test {
  protected:
-  virtual void SetUp() {
+  void SetUp() override {
     upload_callback_count = 0;
     upload_callback = base::Bind(&FakeAttachmentUploaderTest::Increment,
                                  base::Unretained(this),
                                  &upload_callback_count);
   }
   base::MessageLoop message_loop;
   FakeAttachmentUploader uploader;
   int upload_callback_count;
   AttachmentUploader::UploadCallback upload_callback;
 
@@ skipping 16 matching lines @@
   Attachment attachment2 = Attachment::Create(some_data);
   Attachment attachment3 = Attachment::Create(some_data);
   uploader.UploadAttachment(attachment1, upload_callback);
   uploader.UploadAttachment(attachment2, upload_callback);
   uploader.UploadAttachment(attachment3, upload_callback);
   message_loop.RunUntilIdle();
   EXPECT_EQ(upload_callback_count, 3);
 }
 
 }  // namespace syncer