Got disabled in chromium 71 upgrade https://github.com/electron/electron/commit/798b2a3ffd55c477af6258f0afb71000c9f8ecde

/cc @brenca @codebytere 
atom/browser/osr/osr_web_contents_view.h
blink::WebDragOperationsMask allowed_ops,
                     const gfx::ImageSkia& image,
                     const gfx::Vector2d& image_offset,
                     const content::DragEventSourceInfo& event_info,
                     content::RenderWidgetHostImpl* source_rwh) override;
  void UpdateDragCursor(blink::WebDragOperation operation) override;
  void SetPainting(bool painting);
  bool IsPainting() const;
  void SetFrameRate(int frame_rate);
  int GetFrameRate() const;
 private:
#if defined(OS_MACOSX)
  void PlatformCreate();
  void PlatformDestroy();
#endif
  OffScreenRenderWidgetHostView* GetView() const;
  NativeWindow* native_window_;
  const bool transparent_;
  bool painting_ = true;
  int frame_rate_ = 60;
  OnPaintCallback callback_;
  
  content::WebContents* web_contents_ = nullptr;
#if defined(OS_MACOSX)
  OffScreenView* offScreenView_;
#endif
};
}  
#endif