Standardize usage of virtual/override/final in extensions/

extensions/browser/process_map.h

 // Copyright 2013 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.
 
 #ifndef EXTENSIONS_BROWSER_PROCESS_MAP_H_
 #define EXTENSIONS_BROWSER_PROCESS_MAP_H_
 
 #include <set>
 #include <string>
 
@@ skipping 57 matching lines @@
 //    RenderProcessHost::FromID() and check the profile of the resulting object.
 //
 // TODO(aa): The above warnings suggest this class could use improvement :).
 //
 // TODO(kalman): This class is not threadsafe, but is used on both the UI and
 //               IO threads. Somebody should fix that, either make it
 //               threadsafe or enforce single thread. Investigation required.
 class ProcessMap : public KeyedService {
  public:
   ProcessMap();
-  virtual ~ProcessMap();
+  ~ProcessMap() override;
 
   // Returns the instance for |browser_context|. An instance is shared between
   // an incognito and a regular context.
   static ProcessMap* Get(content::BrowserContext* browser_context);
 
   size_t size() const { return items_.size(); }
 
   bool Insert(const std::string& extension_id, int process_id,
               int site_instance_id);
 
@@ skipping 42 matching lines @@
 
   typedef std::set<Item> ItemSet;
   ItemSet items_;
 
   DISALLOW_COPY_AND_ASSIGN(ProcessMap);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_PROCESS_MAP_H_