### Preflight Checklist
<!-- Please ensure you've completed the following steps by replacing [ ] with [x]-->

* [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:**
  * 8.0.0
* **Operating System:**
  * Windows 10 Pro (1709)

### Expected Behavior
Using Notification API in main process with `timeoutType: 'never` I expected that the notification disappears only when the user clicks on it.  

### Actual Behavior
After few seconds the notification disappers.

### To Reproduce

```
  const newNotification = new Notification({title: 'I am a main process Notification!', timeoutType: 'never'})
  newNotification.show()
```

```sh
$ git clone https://github.com/p-fusi/electron-quick-start -b master
$ npm install
$ npm run start
```


shell/browser/notifications/win/windows_toast_notification.cc
const std::wstring& icon_path) {
  ScopedHString tag(L"image");
  if (!tag.success())
    return E_FAIL;
  ComPtr<IXmlNodeList> node_list;
  RETURN_IF_FAILED(doc->GetElementsByTagName(tag, &node_list));
  ComPtr<IXmlNode> image_node;
  RETURN_IF_FAILED(node_list->Item(0, &image_node));
  ComPtr<IXmlNamedNodeMap> attrs;
  RETURN_IF_FAILED(image_node->get_Attributes(&attrs));
  ScopedHString src(L"src");
  if (!src.success())
    return E_FAIL;
  ComPtr<IXmlNode> src_attr;
  RETURN_IF_FAILED(attrs->GetNamedItem(src, &src_attr));
  ScopedHString img_path(icon_path.c_str());
  if (!img_path.success())
    return E_FAIL;
  ComPtr<IXmlText> src_text;
  RETURN_IF_FAILED(doc->CreateTextNode(img_path, &src_text));
  ComPtr<IXmlNode> src_node;
  RETURN_IF_FAILED(src_text.As(&src_node));
  ComPtr<IXmlNode> child_node;
  return src_attr->AppendChild(src_node.Get(), &child_node);
}
HRESULT WindowsToastNotification::GetTextNodeList(ScopedHString* tag,