Offer trampoline to help articles.

This allows other parts of the system internals to re-use common
logic for building help links, and it allows all help links to live
in a single common overlay.

Adds a help link slot for "Android is upgrading" notification.

Bug: 30033319, 30122837
Change-Id: I7dec3e63cfb8c7a8ee9a562cc61cb70f3f99fdae
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 8befc35..76241dd 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -3043,6 +3043,12 @@
             </intent-filter>
         </service>
 
+        <activity android:name=".HelpTrampoline"
+            android:exported="true"
+            android:theme="@android:style/Theme.NoDisplay"
+            android:permission="android.permission.DUMP"
+            android:enabled="@bool/config_has_help" />
+
         <!-- This is the longest AndroidManifest.xml ever. -->
     </application>
 </manifest>