Setting #input based on #base_type is unnecessary

When adding a field of type:

    $form['textarea'] = array(
      '#type' => 'text_format',
      '#format' => 'full_html',
      '#title' => 'Form element'
    );

And the validation of the form fails, the values for these field types are empty.
The problem is caused by /src/Plugin/Alter/ElementInfo.php on line 37:

$element['#input'] = $types[$element['#base_type']]['#input']

When commenting out this line, the problem is solved, but I don't think this is a solid solution?

I added a small example module that exposes a form to demonstrate the problem. Just install it and make sure you are using boostrap as default theme. Then enter a value and submit the form. You will see that the value has magically disappeared :)