Standardize usage of virtual/override/final specifiers.

chrome/browser/browsing_data/browsing_data_file_system_helper_unittest.cc

 // Copyright (c) 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 "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file_util.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 52 matching lines @@
  public:
   BrowsingDataFileSystemHelperTest() {
     profile_.reset(new TestingProfile());
 
     helper_ = BrowsingDataFileSystemHelper::Create(
         BrowserContext::GetDefaultStoragePartition(profile_.get())->
             GetFileSystemContext());
     base::MessageLoop::current()->RunUntilIdle();
     canned_helper_ = new CannedBrowsingDataFileSystemHelper(profile_.get());
   }
-  virtual ~BrowsingDataFileSystemHelperTest() {
+  ~BrowsingDataFileSystemHelperTest() override {
     // Avoid memory leaks.
     profile_.reset();
     base::MessageLoop::current()->RunUntilIdle();
   }
 
   TestingProfile* GetProfile() {
     return profile_.get();
   }
 
   // Blocks on the current MessageLoop until Notify() is called.
@@ skipping 215 matching lines @@
 // extension and devtools schemes.
 TEST_F(BrowsingDataFileSystemHelperTest, IgnoreExtensionsAndDevTools) {
   ASSERT_TRUE(canned_helper_->empty());
   canned_helper_->AddFileSystem(kOriginExt, kTemporary, 0);
   ASSERT_TRUE(canned_helper_->empty());
   canned_helper_->AddFileSystem(kOriginDevTools, kTemporary, 0);
   ASSERT_TRUE(canned_helper_->empty());
 }
 
 }  // namespace