title: Elevation shadow won't show on device only on preview
body: <p>I am trying to implement a drop shadow effect to my layout and decided to go with the elevation option.</p>
  
  <p>But what I end up with in the Android Studio preview doesn't show up on the device for some reason. I will attach screenshot of Android Studio preview and device. And I will provide the code I have used.</p>
  
  <p>[<img src="https://i.stack.imgur.com/OA7bG.png" alt="1]"> <a href="https://i.stack.imgur.com/yelti.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yelti.jpg" alt="enter image description here"></a></p>
  
  <pre><code>&lt;shape xmlns:android="http://schemas.android.com/apk/res/android"
      android:shape="rectangle"&gt;
      &lt;solid android:color="#90000000" /&gt;
      &lt;corners android:radius="10dp" /&gt;
  &lt;/shape&gt;
  
  
  &lt;RelativeLayout
      android:outlineProvider="bounds"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:gravity="center"
      android:layout_gravity="center"
      android:paddingLeft="40dp"
      android:paddingRight="40dp"
      android:paddingTop="20dp"
      android:paddingBottom="20dp"
      android:clipToPadding="false"&gt;
  
  &lt;RelativeLayout
      android:layout_width="300dp"
      android:layout_height="300dp"
      android:background="@drawable/button_shadow"
      android:elevation="30dp"
      /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>