Enable clang style plugin in webrtc/modules/desktop_capture

webrtc/modules/desktop_capture/screen_capturer_mock_objects.h

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 16 matching lines @@
   MOCK_METHOD1(GetScreenList, bool(ScreenList* screens));
   MOCK_METHOD1(SelectScreen, bool(ScreenId id));
 
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(MockScreenCapturer);
 };
 
 class MockScreenCapturerCallback : public ScreenCapturer::Callback {
  public:
   MockScreenCapturerCallback() {}
-  virtual ~MockScreenCapturerCallback() {}
+  ~MockScreenCapturerCallback() override {}
 
   MOCK_METHOD2(OnCaptureResultPtr,
                void(DesktopCapturer::Result result,
                     std::unique_ptr<DesktopFrame>* frame));
   void OnCaptureResult(DesktopCapturer::Result result,
                        std::unique_ptr<DesktopFrame> frame) override {
     OnCaptureResultPtr(result, &frame);
   }
 
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(MockScreenCapturerCallback);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_MOCK_OBJECTS_H_