title: How can I apply notch curve to Widget?
body: <p>I have a design as you can see below and the question is how can I apply this notch effect on Arrow ? Is there any easy way to do it just like in Floating Action Button ? Thanks in advance.</p>
  <p><a href="https://i.stack.imgur.com/ei61Y.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ei61Y.png" alt="enter image description here" /></a></p>