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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
int stream_id,
      InspectableWebContents* bindings,
      const network::ResourceRequest& resource_request,
      const net::NetworkTrafficAnnotationTag& traffic_annotation,
      URLLoaderFactoryHolder url_loader_factory,
      DispatchCallback callback,
      base::TimeDelta delay)
      : stream_id_(stream_id),
        bindings_(bindings),
        resource_request_(resource_request),
        traffic_annotation_(traffic_annotation),
        loader_(network::SimpleURLLoader::Create(
            std::make_unique<network::ResourceRequest>(resource_request),
            traffic_annotation)),
        url_loader_factory_(std::move(url_loader_factory)),
        callback_(std::move(callback)),
        retry_delay_(delay) {
    loader_->SetOnResponseStartedCallback(base::BindOnce(
        &NetworkResourceLoader::OnResponseStarted, base::Unretained(this)));
    timer_.Start(FROM_HERE, delay,
                 base::BindRepeating(&NetworkResourceLoader::DownloadAsStream,
                                     base::Unretained(this)));
  }
  NetworkResourceLoader(const NetworkResourceLoader&) = delete;
  NetworkResourceLoader& operator=(const NetworkResourceLoader&) = delete;
 private:
  void DownloadAsStream() {
    loader_->DownloadAsStream(url_loader_factory_.get(), this);
  }
  base::TimeDelta GetNextExponentialBackoffDelay(const base::TimeDelta& delta) {