title: Chrome 59 Incognito session doesn't expose "Allow" for Notification content settings and defaults to "Blocked" when permission requested through API
body: <p>Chrome <code>Version 59.0.3071.109 (Official Build) (64-bit)</code> (at least on OSX) behaves differently from 58 in that in an <strong>incognito session</strong>, a call to request permission through the browser Notification API does not show the user the permission request popup; instead, it will automatically and silently set the permission from <code>default</code> to <code>blocked</code>. </p>
  
  <p>Furthermore, in the the normal content settings UI beside the URL bar, the option to to "Always allow on this site" is missing from the Notification Permission option dropdown. </p>
  
  <p>How can I allow some content like notifications in an Chrome v59 specifically for an incognito session?</p>