<!--  As an open source project with a dedicated but small maintainer team, it can sometimes take a long time for issues to be addressed so please be patient and we will get back to you as soon as we can.
-->

### Preflight Checklist
<!-- Please ensure you've completed the following steps by replacing [ ] with [x]-->

* [x] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
* [x] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
* [x] I have searched the issue tracker for an issue that matches the one I want to file, without success.

### Issue Details

* **Electron Version:**
  * 12.0.0-beta.1 to 12.0.0-beta.6
* **Operating System:**
  * Windows 10 (2004) 
* **Last Known Working Electron version:**
  * 11.x.x (all of them)

### Expected Behavior
Click on Menu Item opens the submenu of this item

### Actual Behavior
Clicking on menu set with Menu.setApplicationMenu(Menu.buildFromTemplate(topLevelItems)); is not possible. Pressing "ALT" Highlights the menu but nothing more happens

### To Reproduce
Build Application with menu
shell/browser/ui/views/menu_bar.cc
: menu_bar_(menu_bar) {}
MenuBarColorUpdater::~MenuBarColorUpdater() = default;
void MenuBarColorUpdater::OnDidChangeFocus(views::View* focused_before,
                                           views::View* focused_now) {
  if (menu_bar_) {
    
    const auto had_focus = menu_bar_->has_focus_;
    menu_bar_->has_focus_ = focused_now != nullptr;
    if (menu_bar_->has_focus_ != had_focus)
      menu_bar_->UpdateViewColors();
  }
}
MenuBar::MenuBar(RootView* window)
    : background_color_(kDefaultColor),
      window_(window),
      color_updater_(new MenuBarColorUpdater(this)) {
  RefreshColorCache();
  UpdateViewColors();
  SetFocusBehavior(FocusBehavior::ALWAYS);
  SetLayoutManager(std::make_unique<views::BoxLayout>(
      views::BoxLayout::Orientation::kHorizontal));
  window_->GetFocusManager()->AddFocusChangeListener(color_updater_.get());
}
MenuBar::~MenuBar() {