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

/cc @brenca @codebytere 
atom/browser/osr/osr_web_contents_view.h
#else
class OffScreenView;
#endif
#endif
namespace atom {
class OffScreenWebContentsView : public content::WebContentsView,
                                 public content::RenderViewHostDelegateView,
                                 public NativeWindowObserver {
 public:
  OffScreenWebContentsView(bool transparent, const OnPaintCallback& callback);
  ~OffScreenWebContentsView() override;
  void SetWebContents(content::WebContents*);
  void SetNativeWindow(NativeWindow* window);
  
  void OnWindowResize() override;
  void OnWindowClosed() override;
  gfx::Size GetSize();
  
  gfx::NativeView GetNativeView() const override;