### 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
return ID() == ontents->ID();
}
void WebContents::LoadURL(const GURL& url,
                          const gin_helper::Dictionary& options) {
  if (!url.is_valid() || url.spec().size() > url::kMaxURLChars) {
    Emit("did-fail-load", static_cast<int>(net::ERR_INVALID_URL),
         net::ErrorToShortString(net::ERR_INVALID_URL),
         url.possibly_invalid_spec(), true);
    return;
  }
  content::NavigationController::LoadURLParams params(url);
  if (!options.Get("httpReferrer", &params.referrer)) {
    GURL http_referrer;
    if (options.Get("httpReferrer", &http_referrer))
      params.referrer =
          content::Referrer(http_referrer.GetAsReferrer(),
                            network::mojom::ReferrerPolicy::kDefault);
  }
  std::string user_agent;
  if (options.Get("userAgent", &user_agent))
    ontents()->SetUserAgentOverride(
        blink::UserAgentOverride::UserAgentOnly(user_agent), false);
  std::string extra_headers;
  if (options.Get("extraHeaders", &extra_headers))
    params.extra_headers = extra_headers;
  scoped_refptr<network::ResourceRequestBody> body;
  if (options.Get("postData", &body)) {
    params.post_data = body;
    params.load_type = content::NavigationController::LOAD_TYPE_HTTP_POST;
  }