### 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
if (embedder) {
    NativeWindow* owner_window = nullptr;
    auto* relay = NativeWindowRelay::FromWebContents(embedder->ontents());
    if (relay) {
      owner_window = relay->GetNativeWindow();
    }
    if (owner_window)
      SetOwnerWindow(owner_window);
    content::RenderWidgetHostView* rwhv =
        ontents()->GetRenderWidgetHostView();
    if (rwhv) {
      rwhv->Hide();
      rwhv->Show();
    }
  }
}
void WebContents::SetDevToolsWebContents(const WebContents* devtools) {
  if (managed_ontents())
    managed_ontents()->SetDevToolsWebContents(devtools->ontents());
}
v8::Local<v8::Value> WebContents::GetNativeView(v8::Isolate* isolate) const {
  gfx::NativeView ptr = ontents()->GetNativeView();
  auto buffer = node::Buffer::Copy(isolate, reinterpret_cast<char*>(&ptr),
                                   sizeof(gfx::NativeView));
  if (buffer.IsEmpty())
    return v8::Null(isolate);
  else
    return buffer.ToLocalChecked();
}
v8::Local<v8::Value> WebContents::DevToolsWebContents(v8::Isolate* isolate) {