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### Issue Details
Electron Version: All Version
Operating System: macOS 10.15.3
Last Known Working Electron version: Never

### Bug
The color picker in devtools does not work.
In devtools if you want to change the colors of the CSS code. When you click on a color a color picker is supposed to appear but it does not appear.

### Screenshots
<img width="1013" alt="Capture d’écran 2020-09-07 à 11 42 44" src="https://user-images.githubusercontent.com/70572698/92374841-988ea280-f100-11ea-96be-afc93f6dd645.png">

shell/browser/api/electron_api_web_contents.h
void StartPainting();
  void StopPainting();
  bool IsPainting() const;
  void SetFrameRate(int frame_rate);
  int GetFrameRate() const;
#endif
  void Invalidate();
  gfx::Size GetSizeForNewRenderView(content::WebContents*) override;
  
  void SetZoomLevel(double level);
  double GetZoomLevel() const;
  void SetZoomFactor(gin_helper::ErrorThrower thrower, double factor);
  double GetZoomFactor() const;
  
  void OnEnterFullscreenModeForTab(
      content::RenderFrameHost* requesting_frame,
      const blink::mojom::FullscreenOptions& options,
      bool allowed);
  
  void OnCreateWindow(const GURL& target_url,
                      const content::Referrer& referrer,
                      const std::string& frame_name,
                      WindowOpenDisposition disposition,
                      const std::string& features,
                      const scoped_refptr<network::ResourceRequestBody>& body);
  
  std::vector<base::FilePath> GetPreloadPaths() const;
  
  v8::Local<v8::Value> GetWebPreferences(v8::Isolate* isolate) const;
  v8::Local<v8::Value> GetLastWebPreferences(v8::Isolate* isolate) const;