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

chrome/browser/ui/cocoa/download/download_item_mac.h

Index: chrome/browser/ui/cocoa/download/download_item_mac.h
diff --git a/chrome/browser/ui/cocoa/download/download_item_mac.h b/chrome/browser/ui/cocoa/download/download_item_mac.h
index 14d80e5c535e4e42536d17dd8be9b6d148749d83..a6e430de18eea91bc3fc034f384a185da612e79b 100644
--- a/chrome/browser/ui/cocoa/download/download_item_mac.h
+++ b/chrome/browser/ui/cocoa/download/download_item_mac.h
@@ -29,12 +29,12 @@ class DownloadItemMac : content::DownloadItem::Observer {
                   DownloadItemController* controller);
 
   // Destructor.
-  virtual ~DownloadItemMac();
+  ~DownloadItemMac() override;
 
   // content::DownloadItem::Observer implementation
-  virtual void OnDownloadUpdated(content::DownloadItem* download) override;
-  virtual void OnDownloadOpened(content::DownloadItem* download) override;
-  virtual void OnDownloadDestroyed(content::DownloadItem* download) override;
+  void OnDownloadUpdated(content::DownloadItem* download) override;
+  void OnDownloadOpened(content::DownloadItem* download) override;
+  void OnDownloadDestroyed(content::DownloadItem* download) override;
 
   DownloadItemModel* download_model() { return &download_model_; }