Standardize usage of virtual/override/final in content/browser/

content/browser/streams/stream_handle_impl.h

Index: content/browser/streams/stream_handle_impl.h
diff --git a/content/browser/streams/stream_handle_impl.h b/content/browser/streams/stream_handle_impl.h
index f642ad5bd3fc668c313632008e053eecc5962797..d2bd94def8e993fb23772a39263b6c0ef49f10fc 100644
--- a/content/browser/streams/stream_handle_impl.h
+++ b/content/browser/streams/stream_handle_impl.h
@@ -21,12 +21,12 @@ class Stream;
 class StreamHandleImpl : public StreamHandle {
  public:
   StreamHandleImpl(const base::WeakPtr<Stream>& stream);
-  virtual ~StreamHandleImpl();
+  ~StreamHandleImpl() override;
 
  private:
   // StreamHandle overrides
-  virtual const GURL& GetURL() override;
-  virtual void AddCloseListener(const base::Closure& callback) override;
+  const GURL& GetURL() override;
+  void AddCloseListener(const base::Closure& callback) override;
 
   base::WeakPtr<Stream> stream_;
   GURL url_;