title: How to rotate floating action button without rotating shadow?
body: <p>I rotate the FAB in such a simple way:</p>
  
  <pre><code>fab.startAnimation(AnimationUtils.loadAnimation(this, R.anim.rotate));
  </code></pre>
  
  <p><em>rotate.xml</em>:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;set xmlns:android="http://schemas.android.com/apk/res/android"&gt;
      &lt;rotate
          android:fromDegrees="0"
          android:toDegrees="360"
          android:pivotX="50%"
          android:pivotY="50%"
          android:duration="1000"/&gt;
  &lt;/set&gt;
  </code></pre>
  
  <p>This works, but together with the FAB its shadow rotates. But I need only the FAB to rotate (or even its src image, if there's any difference).</p>