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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.cc
const std::string& type,
    const base::FilePath& file_system_path) {
  base::FilePath path = file_system_path;
  if (path.empty()) {
    std::vector<base::FilePath> paths;
    file_dialog::DialogSettings settings;
    settings.parent_window = owner_window();
    settings.force_detached = offscreen_;
    settings.properties = file_dialog::OPEN_DIALOG_OPEN_DIRECTORY;
    if (!file_dialog::ShowOpenDialogSync(settings, &paths))
      return;
    path = paths[0];
  }
  std::string file_system_id =
      RegisterFileSystem(GetDevToolsWebContents(), path);
  if (IsDevToolsFileSystemAdded(GetDevToolsWebContents(), path.AsUTF8Unsafe()))
    return;
  FileSystem file_system = CreateFileSystemStruct(
      GetDevToolsWebContents(), file_system_id, path.AsUTF8Unsafe(), type);
  std::unique_ptr<base::DictionaryValue> file_system_value(
      CreateFileSystemValue(file_system));
  auto* pref_service = GetPrefService(GetDevToolsWebContents());
  DictionaryPrefUpdate update(pref_service, prefs::kDevToolsFileSystemPaths);
  update.Get()->SetWithoutPathExpansion(path.AsUTF8Unsafe(),
                                        std::make_unique<base::Value>(type));
  inspectable_ontents_->CallClientFunction(
      "DevToolsAPI.fileSystemAdded", nullptr, file_system_value.get(), nullptr);
}
void WebContents::DevToolsRemoveFileSystem(