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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/ui/inspectable_web_contents.cc
const int stream_id_;
  InspectableWebContents* const bindings_;
  const network::ResourceRequest resource_request_;
  const net::NetworkTrafficAnnotationTag traffic_annotation_;
  std::unique_ptr<network::SimpleURLLoader> loader_;
  URLLoaderFactoryHolder url_loader_factory_;
  DispatchCallback callback_;
  scoped_refptr<net::HttpResponseHeaders> response_headers_;
  base::OneShotTimer timer_;
  base::TimeDelta retry_delay_;
};
InspectableWebContentsView* CreateInspectableContentsView(
    InspectableWebContents* inspectable_web_contents);
const InspectableWebContents::List& InspectableWebContents::GetAll() {
  return g_web_contents_instances_;
}
void InspectableWebContents::RegisterPrefs(PrefRegistrySimple* registry) {
  registry->RegisterDictionaryPref(kDevToolsBoundsPref,
                                   RectToDictionary(gfx::Rect(0, 0, 800, 600)));
  registry->RegisterDoublePref(kDevToolsZoomPref, 0.);
  registry->RegisterDictionaryPref(kDevToolsPreferences);
}
InspectableWebContents::InspectableWebContents(