Patch to backup settings using BackupAgentHelper

Integration of external patch:
https://review.source.android.com/#change,18649

Change-Id: I518625ff92ddb0a3e43d81a88ba2b2a2634fff3a
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 73e14c7..b100caa 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -40,7 +40,11 @@
     <application android:name="CalendarApplication"
             android:label="@string/app_label" android:icon="@mipmap/app_icon"
             android:taskAffinity="android.task.calendar"
-            android:hardwareAccelerated="true" >
+            android:hardwareAccelerated="true"
+            android:backupAgent="com.android.calendar.CalendarBackupAgent" >
+
+        <meta-data android:name="com.google.android.backup.api_key"
+                android:value="AEdPqrEAAAAIM256oVOGnuSel5QKDpL8je_T65ZI8rFnDinssA" />
 
         <activity
             android:name="AllInOneActivity"