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

chrome/browser/renderer_host/chrome_render_widget_host_view_mac_history_swiper_browsertest.mm

 // 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 <Cocoa/Cocoa.h>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/mac/scoped_nsobject.h"
 #import "base/mac/sdk_forward_declarations.h"
@@ skipping 64 matching lines @@
       : event_queue_(), touch_(CGPointMake(0, 0)) {
     const base::FilePath base_path(FILE_PATH_LITERAL("scroll"));
     url1_ = ui_test_utils::GetTestUrl(
         base_path, base::FilePath(FILE_PATH_LITERAL("text.html")));
     url2_ = ui_test_utils::GetTestUrl(
         base_path, base::FilePath(FILE_PATH_LITERAL("blank.html")));
     url_iframe_ = ui_test_utils::GetTestUrl(
         base_path, base::FilePath(FILE_PATH_LITERAL("iframe.html")));
   }
 
-  virtual void SetUpOnMainThread() override {
+  void SetUpOnMainThread() override {
     event_queue_.reset([[NSMutableArray alloc] init]);
     touch_ = CGPointMake(0.5, 0.5);
 
     // Ensure that the navigation stack is not empty.
     ui_test_utils::NavigateToURL(browser(), url1_);
     ASSERT_EQ(url1_, GetWebContents()->GetURL());
     ui_test_utils::NavigateToURL(browser(), url2_);
     ASSERT_EQ(url2_, GetWebContents()->GetURL());
   }
 
-  virtual void TearDownOnMainThread() override {
-    event_queue_.reset();
-  }
+  void TearDownOnMainThread() override { event_queue_.reset(); }
 
  protected:
   // Returns the active web contents.
   content::WebContents* GetWebContents() {
     return browser()->tab_strip_model()->GetActiveWebContents();
   }
 
   // Returns the value of |query| from Javascript as an int.
   int GetScriptIntValue(const std::string& query) {
     int value = 0;
@@ skipping 613 matching lines @@
   QueueTouch(
       DEPLOYMENT_TOUCHES_MOVED, NSEventTypeEndGesture, NSMouseEventSubtype, NO);
   QueueGestureEnd();
   QueueTouch(
       DEPLOYMENT_TOUCHES_ENDED, NSEventTypeEndGesture, NSMouseEventSubtype, NO);
   QueueTrackpadScroll(0, 0, NSEventPhaseEnded, YES);
 
   RunQueuedEvents();
   ExpectUrlAndOffset(url1_, 0);
 }