title: Background color in Dialog does not show properly
body: <p>I used Dialog in my app and sets its layout from xml. When I use the below code it works properly (background color).</p>
  
  <pre><code> &lt;LinearLayout
      android:layout_width="match_parent"
      android:layout_height="@dimen/size40"
      android:orientation="vertical"
      android:background="@color/colorPrimary"&gt;
  
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>But when I use the below code it does not work properly. I tested it in Hwawei TIT-AL00 (Android version 5.1)</p>
  
  <pre><code> &lt;LinearLayout
      android:layout_width="match_parent"
      android:layout_height="@dimen/size40"
      android:orientation="vertical"
      android:background="?android:colorPrimary"&gt;
  
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>Its background color does not show. My project minSdkVersion is 21. I need to use</p>
  
  <pre><code>android:background="?android:colorPrimary
  </code></pre>
  
  <p>because of my some requirements. Dialog has no custom style and The style I used in activity class is:</p>
  
  <pre><code>&lt;style name="AppTheme" parent="Theme.AppCompat.DayNight.NoActionBar"&gt;
      &lt;!-- Customize your theme here. --&gt;
      &lt;item name="colorPrimary"&gt;@color/colorPrimary&lt;/item&gt;
      &lt;item name="colorPrimaryDark"&gt;@color/colorPrimaryDark&lt;/item&gt;
      &lt;item name="colorAccent"&gt;@color/colorAccent&lt;/item&gt;
      &lt;item name="android:windowNoTitle"&gt;true&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>