Standardize usage of virtual/override/final in media/

media/base/video_frame_unittest.cc

Index: media/base/video_frame_unittest.cc
diff --git a/media/base/video_frame_unittest.cc b/media/base/video_frame_unittest.cc
index 08d02bf90628fafcc89ce6aa8b319b6238882abf..38485c2e1ce65e390fdc1f34ae61039728608236 100644
--- a/media/base/video_frame_unittest.cc
+++ b/media/base/video_frame_unittest.cc
@@ -271,9 +271,9 @@ namespace {
 class SyncPointClientImpl : public VideoFrame::SyncPointClient {
  public:
   explicit SyncPointClientImpl(uint32 sync_point) : sync_point_(sync_point) {}
-  virtual ~SyncPointClientImpl() {}
-  virtual uint32 InsertSyncPoint() override { return sync_point_; }
-  virtual void WaitSyncPoint(uint32 sync_point) override {}
+  ~SyncPointClientImpl() override {}
+  uint32 InsertSyncPoint() override { return sync_point_; }
+  void WaitSyncPoint(uint32 sync_point) override {}
 
  private:
   uint32 sync_point_;