Standardize usage of virtual/override/final in media/

media/base/stream_parser_buffer.h

Index: media/base/stream_parser_buffer.h
diff --git a/media/base/stream_parser_buffer.h b/media/base/stream_parser_buffer.h
index 6897de5e8c7e6f5df6cb0396cfb4191b33b2b059..1651dce48559af96c013ffe1c8c47817fef04a9d 100644
--- a/media/base/stream_parser_buffer.h
+++ b/media/base/stream_parser_buffer.h
@@ -169,14 +169,14 @@ class MEDIA_EXPORT StreamParserBuffer : public DecoderBuffer {
     return preroll_buffer_;
   }
 
-  virtual void set_timestamp(base::TimeDelta timestamp) override;
+  void set_timestamp(base::TimeDelta timestamp) override;
 
  private:
   StreamParserBuffer(const uint8* data, int data_size,
                      const uint8* side_data, int side_data_size,
                      bool is_keyframe, Type type,
                      TrackId track_id);
-  virtual ~StreamParserBuffer();
+  ~StreamParserBuffer() override;
 
   bool is_keyframe_;
   DecodeTimestamp decode_timestamp_;