Update {virtual,override} to follow C++11 style in media.

media/base/fake_audio_render_callback.h

Index: media/base/fake_audio_render_callback.h
diff --git a/media/base/fake_audio_render_callback.h b/media/base/fake_audio_render_callback.h
index 7805fc65c62ee25d317c765424c26ab8fbfd03af..65d7df2366b1598f1e6335cda11dbecbc807f350 100644
--- a/media/base/fake_audio_render_callback.h
+++ b/media/base/fake_audio_render_callback.h
@@ -22,17 +22,16 @@ class FakeAudioRenderCallback
   // where x = [|number_of_frames| * m, |number_of_frames| * (m + 1)] and m =
   // the number of Render() calls fulfilled thus far.
   explicit FakeAudioRenderCallback(double step);
-  virtual ~FakeAudioRenderCallback();
+  ~FakeAudioRenderCallback() override;
 
   // Renders a sine wave into the provided audio data buffer.  If |half_fill_|
   // is set, will only fill half the buffer.
-  virtual int Render(AudioBus* audio_bus,
-                     int audio_delay_milliseconds) override;
+  int Render(AudioBus* audio_bus, int audio_delay_milliseconds) override;
   MOCK_METHOD0(OnRenderError, void());
 
   // AudioTransform::ProvideAudioTransformInput implementation.
-  virtual double ProvideInput(AudioBus* audio_bus,
-                              base::TimeDelta buffer_delay) override;
+  double ProvideInput(AudioBus* audio_bus,
+                      base::TimeDelta buffer_delay) override;
 
   // Toggles only filling half the requested amount during Render().
   void set_half_fill(bool half_fill) { half_fill_ = half_fill; }