title: FloatingActionButton, square button below API level 17
body: <p>I am using android.support.design.widget.FloatingActionButton from the new Design Support library 22.2.0, in my layout file. It is working fine but it shows a square button below API level 17</p>
  
  <p><img src="https://i.stack.imgur.com/VcP6T.png" alt="API 16"></p>