title: Android studio do not show devices for flutter
body: <p>I am new to Flutter and android studio, I followed the instructions of flutter.io ,  I created a blank app, and while I try to run I am unable to see the device lists. but it is available in device manager 
  Please see the screenshot.<a href="https://i.stack.imgur.com/uB5ll.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uB5ll.png" alt="enter image description here"></a></p>