Standardize usage of virtual/override/final in remoting/

remoting/host/ipc_audio_capturer.h

Index: remoting/host/ipc_audio_capturer.h
diff --git a/remoting/host/ipc_audio_capturer.h b/remoting/host/ipc_audio_capturer.h
index 57d2cadc7c236f510cebb6bc34e5dfedc2d34816..d0bdbe3fc7b4772bf329f5349cb60519a7367f98 100644
--- a/remoting/host/ipc_audio_capturer.h
+++ b/remoting/host/ipc_audio_capturer.h
@@ -20,12 +20,12 @@ class IpcAudioCapturer : public AudioCapturer {
  public:
   explicit IpcAudioCapturer(
       scoped_refptr<DesktopSessionProxy> desktop_session_proxy);
-  virtual ~IpcAudioCapturer();
+  ~IpcAudioCapturer() override;
 
   // AudioCapturer interface.
-  virtual bool Start(const PacketCapturedCallback& callback) override;
-  virtual void Stop() override;
-  virtual bool IsStarted() override;
+  bool Start(const PacketCapturedCallback& callback) override;
+  void Stop() override;
+  bool IsStarted() override;
 
   // Called by DesktopSessionProxy when an audio packet is received.
   void OnAudioPacket(scoped_ptr<AudioPacket> packet);