title: Displaying notification badge on BottomNavigationBar's Icon
body: <p>I'd like to display notification badge (a colored <strong>marble</strong>) on the <strong>top right corner</strong> of BottomNavigationBar's <strong>Icon</strong> widget when a new message has arrived in the inbox tab. It is similar to <a href="https://developer.android.com/preview/features/notification-badges.html" rel="noreferrer">https://developer.android.com/preview/features/notification-badges.html</a> but for my case it is displayed in-app.</p>
  
  <p>Any tips to paint the overlay on existing icon to create a <strong>custom</strong> Icon class?</p>