title: Android “elevation” is not showing a shadow under a CustomView
body: <p>I Have a CustomView working on pre-Lollipop, now I tried to apply <code>android:elevation</code> and <code>android:translateZ</code> on Lollipop devices but doesn't seems to work.</p>
  
  <pre><code>&lt;com.example.CustomView
      android:id="@+id/myview"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:elevation="10dp"&gt;
  &lt;/com.example.CustomView&gt;
  </code></pre>
  
  <p>What i missing?</p>