Docs: Fixed a wrong adb command example

Bug: 28310568

Change-Id: Ie727a7dcbcba23a6fed36ff6b1572096d3cc7832
diff --git a/docs/html/preview/features/background-optimization.jd b/docs/html/preview/features/background-optimization.jd
index ec02328..3c33b9d 100644
--- a/docs/html/preview/features/background-optimization.jd
+++ b/docs/html/preview/features/background-optimization.jd
@@ -379,7 +379,7 @@
 
   <li style="list-style: none; display: inline">
 <pre class="no-pretty-print">
-{@code $ adb shell cmd appops set RUN_IN_BACKGROUND ignore}
+{@code $ adb shell cmd appops set &lt;package&gt; RUN_IN_BACKGROUND ignore}
 </pre>
   </li>
 
@@ -389,7 +389,7 @@
 
   <li style="list-style: none; display: inline">
 <pre class="no-pretty-print">
-{@code $ adb shell cmd appops set RUN_IN_BACKGROUND allow}
+{@code $ adb shell cmd appops set &lt;package&gt; RUN_IN_BACKGROUND allow}
 </pre>
   </li>
-</ul>
\ No newline at end of file
+</ul>