title: Antd Custom validator and validateFields are not working together as expected
body: <p>I'm working on a form (<code>Ant Design</code> <code>&lt;Form&gt;</code>) where I want a custom validation of phone number (as it depends on <code>country</code> field and has some extra logic), and other fields validated by <code>antd</code> built-in features, so when user submits the form I want all fields to be validated with <code>validateFields()</code> passed as an array of field names showing validation errors as usual (red message underneath and an error message in console), but all I'm getting is just a warning message in the console.</p>
  
  <p>Here's a minimal reproduction </p>
  
  <p><a href="https://codesandbox.io/s/confident-goodall-4f0bx?fontsize=14&amp;hidenavigation=1&amp;theme=dark" rel="nofollow noreferrer"><img src="https://codesandbox.io/static/img/play-codesandbox.svg" alt="Edit confident-goodall-4f0bx"></a></p>
  
  <p>Am I missing something about how <code>validator</code> function works?</p>