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

content/browser/media/capture/desktop_capture_device.h

Index: content/browser/media/capture/desktop_capture_device.h
diff --git a/content/browser/media/capture/desktop_capture_device.h b/content/browser/media/capture/desktop_capture_device.h
index 006848fab1b7c4d750a29a2920a0952fde59904e..a9c3f000b3c9c2e80fc6fb2d5f7f2f40eb85e6b3 100644
--- a/content/browser/media/capture/desktop_capture_device.h
+++ b/content/browser/media/capture/desktop_capture_device.h
@@ -35,12 +35,12 @@ class CONTENT_EXPORT DesktopCaptureDevice : public media::VideoCaptureDevice {
   static scoped_ptr<media::VideoCaptureDevice> Create(
       const DesktopMediaID& source);
 
-  virtual ~DesktopCaptureDevice();
+  ~DesktopCaptureDevice() override;
 
   // VideoCaptureDevice interface.
-  virtual void AllocateAndStart(const media::VideoCaptureParams& params,
-                                scoped_ptr<Client> client) override;
-  virtual void StopAndDeAllocate() override;
+  void AllocateAndStart(const media::VideoCaptureParams& params,
+                        scoped_ptr<Client> client) override;
+  void StopAndDeAllocate() override;
 
   // Set the platform-dependent window id for the notification window.
   void SetNotificationWindowId(gfx::NativeViewId window_id);