Standardize usage of virtual/override/final in components/

components/visitedlink/renderer/visitedlink_slave.h

Index: components/visitedlink/renderer/visitedlink_slave.h
diff --git a/components/visitedlink/renderer/visitedlink_slave.h b/components/visitedlink/renderer/visitedlink_slave.h
index 5131e65bd4104cf674dad4774c6b0eadf7d8c4d4..730f789230bd1d9857c90809dc38368c11ad5d4f 100644
--- a/components/visitedlink/renderer/visitedlink_slave.h
+++ b/components/visitedlink/renderer/visitedlink_slave.h
@@ -18,10 +18,10 @@ class VisitedLinkSlave : public VisitedLinkCommon,
                          public content::RenderProcessObserver {
  public:
   VisitedLinkSlave();
-  virtual ~VisitedLinkSlave();
+  ~VisitedLinkSlave() override;
 
   // RenderProcessObserver implementation.
-  virtual bool OnControlMessageReceived(const IPC::Message& message) override;
+  bool OnControlMessageReceived(const IPC::Message& message) override;
 
   // Message handlers.
   void OnUpdateVisitedLinks(base::SharedMemoryHandle table);