Standardize usage of virtual/override/final in components/

components/tracing/child_trace_message_filter.h

Index: components/tracing/child_trace_message_filter.h
diff --git a/components/tracing/child_trace_message_filter.h b/components/tracing/child_trace_message_filter.h
index 2f79d0e56c35962a11136d7fe13970ed53b2213d..daa00ee3bdad0d8f5b7441c3f005689dbd9f273e 100644
--- a/components/tracing/child_trace_message_filter.h
+++ b/components/tracing/child_trace_message_filter.h
@@ -21,12 +21,12 @@ class ChildTraceMessageFilter : public IPC::MessageFilter {
   explicit ChildTraceMessageFilter(base::MessageLoopProxy* ipc_message_loop);
 
   // IPC::MessageFilter implementation.
-  virtual void OnFilterAdded(IPC::Sender* sender) override;
-  virtual void OnFilterRemoved() override;
-  virtual bool OnMessageReceived(const IPC::Message& message) override;
+  void OnFilterAdded(IPC::Sender* sender) override;
+  void OnFilterRemoved() override;
+  bool OnMessageReceived(const IPC::Message& message) override;
 
  protected:
-  virtual ~ChildTraceMessageFilter();
+  ~ChildTraceMessageFilter() override;
 
  private:
   // Message handlers.