### 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
WebConbContents::From(content::WebContents* ontents) {
  if (!ontents)
    return nullptr;
  UserDataLink* data = static_cast<UserDataLink*>(
      ontents->GetUserData(kElectronApiWebContentsKey));
  return data ? data->ontents.get() : nullptr;
}
 static
gin::HContents> WebContents::FromOrCreate(
    v8::Isolate* isolate,
    content::WebContents* ontents) {
  WebContents* api_ontents = From(ontents);
  if (!api_ontents) {
    api_ontents = new WebContents(isolate, ontents);
    gin_helper::CallMethod(isolate, api_ontents, "_init");
  }
  return gin::CreateHandle(isolate, api_ontents);
}
 static
WebConbContents::FromID(int32_t id) {
  return GetAllWebContents().Lookup(id);
}