### 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
std::unique_ptr<content::WebContents> ontents,
                         Type type)
    : content::WebContentsObserver(ontents.get()),
      type_(type),
      id_(GetAllWebContents().Add(this)),
      weak_factory_(this) {
  DCHECK(type != Type::REMOTE)
      << "Can't take ownership of a remote WebContents";
  auto session = Session::CreateFrom(isolate, GetBrowserContext());
  session_.Reset(isolate, session.ToV8());
  InitWithSessionAndOptions(isolate, std::move(ontents), session,
                            gin::Dictionary::CreateEmpty(isolate));
}
WebContents::WebContents(v8::Isolate* isolate,
                         const gin_helper::Dictionary& options)
    : id_(GetAllWebContents().Add(this)), weak_factory_(this) {
  
  options.Get("backgroundThrottling", &background_throttling_);
  
  options.Get("type", &type_);
#if BUILDFLAG(ENABLE_OSR)
  bool b = false;
  if (options.Get(options::kOffscreen, &b) && b)
    type_ = Type::OFF_SCREEN;
#endif
  
  options.Get("embedder", &embedder_);
  
  options.Get("devTools", &enable_devtools_);