### Preflight Checklist
* [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:**
  * 10.1.1
* **Operating System:**
  * macOS 10.15.4

We recently started launching as hidden on macOS (that is, `show: false` or `browserWindow.hide()` while loading the page, followed by `browserWindow.show()` when the dock icon is clicked). This results in some busted focus behavior on the first activation of the window. The second activation restores it.

### Expected Behavior
The guest page receives a `focus` event on the first activation of the app, when created with `show: false`.

### Actual Behavior
The guest page doesn't receive the first `focus` event. Subsequent activations do trigger a `focus` event.

### To Reproduce
[Electron Fiddle](https://gist.github.com/CharlieHess/c507468cd40630d04f58c6514100b997)

shell/browser/api/electron_api_web_contents.cc
content::WebContents* source) {
  if (!dialog_manager_)
    dialog_manager_ = std::make_unique<ElectronJavaScriptDialogManager>();
  return dialog_manager_.get();
}
void WebContents::OnAudioStateChanged(bool audible) {
  Emit("-audio-state-changed", audible);
}
void WebContents::BeforeUnloadFired(bool proceed,
                                    const base::TimeTicks& proceed_time) {
  
  
}
void WebContents::RenderViewCreated(content::RenderViewHost* render_view_host) {
  if (!background_throttling_)
    render_view_host->SetSchedulerThrottling(false);
}
void WebContents::RenderFrameCreated(
    content::RenderFrameHost* render_frame_host) {
  auto* rwhv = render_frame_host->GetView();
  if (!rwhv)
    return;
  auto* rwh_impl =
      static_cast<content::RenderWidgetHostImpl*>(rwhv->GetRenderWidgetHost());
  if (rwh_impl)
    rwh_impl->disable_hidden_ = !background_throttling_;
}
void WebContents::RenderViewHostChanged(content::RenderViewHost* old_host,