Standardize usage of virtual/override/final in content/

content/public/browser/download_item.h

 // 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.
 //
 // Each download is represented by a DownloadItem, and all DownloadItems
 // are owned by the DownloadManager which maintains a global list of all
 // downloads. DownloadItems are created when a user initiates a download,
 // and exist for the duration of the browser life time.
 //
 // Download observers:
@@ skipping 81 matching lines @@
 
     // Called when the download is being destroyed. This happens after
     // every OnDownloadRemoved() as well as when the DownloadManager is going
     // down.
     virtual void OnDownloadDestroyed(DownloadItem* download) {}
 
    protected:
     virtual ~Observer() {}
   };
 
-  virtual ~DownloadItem() {}
+  ~DownloadItem() override {}
 
   // Observation ---------------------------------------------------------------
 
   virtual void AddObserver(DownloadItem::Observer* observer) = 0;
   virtual void RemoveObserver(DownloadItem::Observer* observer) = 0;
   virtual void UpdateObservers() = 0;
 
   // User Actions --------------------------------------------------------------
 
   // Called when the user has validated the download of a dangerous file.
@@ skipping 216 matching lines @@
   // return |name|. Has no effect on the final target filename.
   virtual void SetDisplayName(const base::FilePath& name) = 0;
 
   // Debug/testing -------------------------------------------------------------
   virtual std::string DebugString(bool verbose) const = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_ITEM_H_