title: What does tools:ignore="UselessParent" mean in the Android XML layout file?
body: <p>The code snippet:</p>
  
  <pre><code> &lt;LinearLayout
          android:id="@+id/fullscreen_content_controls"
          style="?buttonBarStyle"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_gravity="bottom|center_horizontal"
          android:background="@color/black_overlay"
          android:orientation="horizontal"
          tools:ignore="UselessParent" &gt;
  
          &lt;Button
              android:id="@+id/dummy_button"
              style="?buttonBarButtonStyle"
              android:layout_width="0dp"
              android:layout_height="wrap_content"
              android:layout_weight="1"
              android:text="@string/dummy_button" /&gt;
     &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>I'm not sure <code>tools:ignore="UselessParent"</code> means. Does it mean when the lint finds the Button fills the <code>LinearLayout</code>, then the <code>LinearLayout</code> will be removed, and the Button will moved into the parent and let the view hierarchy efficient? Thanks a lot!</p>