### 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.h
void DidStartLoading() override;
  void DidStopLoading() override;
  void DidStartNavigation(
      content::NavigationHandle* navigation_handle) override;
  void DidRedirectNavigation(
      content::NavigationHandle* navigation_handle) override;
  void DidFinishNavigation(
      content::NavigationHandle* navigation_handle) override;
  bool OnMessageReceived(const IPC::Message& message) override;
  void WebContentsDestroyed() override;
  void NavigationEntryCommitted(
      const content::LoadCommittedDetails& load_details) override;
  void TitleWasSet(content::NavigationEntry* entry) override;
  void DidUpdateFaviconURL(
      content::RenderFrameHost* render_frame_host,
      const std::vector<blink::mojom::FaviconURLPtr>& urls) override;
  void PluginCrashed(const base::FilePath& plugin_path,
                     base::ProcessId plugin_pid) override;
  void MediaStartedPlaying(const MediaPlayerInfo& video_type,
                           const content::MediaPlayerId& id) override;
  void MediaStoppedPlaying(
      const MediaPlayerInfo& video_type,
      const content::MediaPlayerId& id,
      content::WebContentsObserver::MediaStoppedReason reason) override;
  void DidChangeThemeColor() override;
  void OnInterfaceRequestFromFrame(
      content::RenderFrameHost* render_frame_host,
      const std::string& interface_name,
      mojo::ScopedMessagePipeHandle* interface_pipe) override;
  void OnCursorChanged(const content::WebCursor& cursor) override;