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

chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc

Index: chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
diff --git a/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc b/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
index d2e545b415dd1f64cb5a462f3a9b3edd8decf8da..438e30a7d21b2d9afa98cdc0fa521f1a0dee617d 100644
--- a/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
+++ b/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
@@ -54,7 +54,7 @@ class MockDownloadsDOMHandler : public DownloadsDOMHandler {
       waiting_list_(false),
       waiting_updated_(false) {
   }
-  virtual ~MockDownloadsDOMHandler() {}
+  ~MockDownloadsDOMHandler() override {}
 
   base::ListValue* downloads_list() { return downloads_list_.get(); }
   base::ListValue* download_updated() { return download_updated_.get(); }
@@ -81,11 +81,9 @@ class MockDownloadsDOMHandler : public DownloadsDOMHandler {
   void reset_download_updated() { download_updated_.reset(); }
 
  protected:
-  virtual content::WebContents* GetWebUIWebContents() override {
-    return NULL;
-  }
+  content::WebContents* GetWebUIWebContents() override { return NULL; }
 
-  virtual void CallDownloadsList(const base::ListValue& downloads) override {
+  void CallDownloadsList(const base::ListValue& downloads) override {
     downloads_list_.reset(downloads.DeepCopy());
     if (waiting_list_) {
       content::BrowserThread::PostTask(content::BrowserThread::UI,
@@ -94,7 +92,7 @@ class MockDownloadsDOMHandler : public DownloadsDOMHandler {
     }
   }
 
-  virtual void CallDownloadUpdated(const base::ListValue& download) override {
+  void CallDownloadUpdated(const base::ListValue& download) override {
     download_updated_.reset(download.DeepCopy());
     if (waiting_updated_) {
       content::BrowserThread::PostTask(content::BrowserThread::UI,
@@ -120,7 +118,7 @@ class DownloadsDOMHandlerTest : public InProcessBrowserTest {
 
   virtual ~DownloadsDOMHandlerTest() {}
 
-  virtual void SetUpOnMainThread() override {
+  void SetUpOnMainThread() override {
     mock_handler_.reset(new MockDownloadsDOMHandler(download_manager()));
     CHECK(downloads_directory_.CreateUniqueTempDir());
     browser()->profile()->GetPrefs()->SetFilePath(