### 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
InitZoomController(ontents(), options);
#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
  extensions::ElectronExtensionWebContentsObserver::CreateForWebContents(
      ontents());
  script_executor_.reset(new extensions::ScriptExecutor(ontents()));
#endif
  registry_.AddInterface(base::BindRepeating(&WebContents::BindElectronBrowser,
                                             base::Unretained(this)));
  receivers_.set_disconnect_handler(base::BindRepeating(
      &WebContents::OnElectronBrowserConnectionError, base::Unretained(this)));
  AutofillDriverFactory::CreateForWebContents(ontents());
  ontents()->SetUserAgentOverride(blink::UserAgentOverride::UserAgentOnly(
                                           GetBrowserContext()->GetUserAgent()),
                                       false);
  if (IsGuest()) {
    NativeWindow* owner_window = nullptr;
    if (embedder_) {
      
      auto* relay =
          NativeWindowRelay::FromWebContents(embedder_->ontents());
      if (relay)
        owner_window = relay->GetNativeWindow();
    }
    if (owner_window)
      SetOwnerWindow(owner_window);
  }
  ontents()->SetUserData(kElectronApiWebContentsKey,
                              std::make_unique<UserDataLink>(GetWeakPtr()));
}
WebContents::~WebContents() {