title: Angular 2 - Form is invalid when browser autofill
body: <p>I have a Login Form which has email and password fields.</p>
  
  <p>I've chosen for browser autofill.</p>
  
  <p>The problems is: When browser autofills login form, both fields are pristine and untouched, so the submit button is disabled.</p>
  
  <p>If I click on disabled button, it enables and fires submit action, what is nice. But the default disabled aspect is pretty bad what can make some users disappointed.</p>
  
  <p>Do you have some ideas about how to deal with?</p>