title: Spinner graphical bug API 21
body: <p>I have one spinner in a fragment that have a very annoying graphical glitch.
  This occurs only on my Nexus 5 with API 21.
  <img src="https://i.stack.imgur.com/Kfnrs.png" alt="enter image description here"></p>
  
  <p>I have try to set spinner.setLayerType(View.LAYER_TYPE_SOFTWARE, null) but the glitch is still present.
  Any ideas?</p>