title: I get an err_cleartext_not_permitted for http
body: <p>I get <code>ERR_CLEARTEXT_NOT_PERMITTED</code> for Android and blank page for iOS when I use <code>http://</code> URLs.</p>
  
  <p><code>https://</code> URLs seem to work.</p>
  
  <p>The very same <code>http://</code> URLs work fine in Chrome.</p>
  
  <p>I recall I had the same problem in native Android as well some year ago.
  Is it possible to tell webview "please use <code>http://</code>. I will take the risk"?</p>
  
  <p>I'm using webview_flutter: ^0.3.2+1</p>