Move some system services to their own sub package.

As a next step they can be moved into separate directories to be
built as separate modules that may or may not be included in a
particular configuration.

Moves AppWidgetService, BackupManagerService, ClipboardService, DevicePolicyMS,
and WallpaperMS.

Change-Id: I33e48d070f38186819d3a1d7a4dc3984b75a9eda
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 8f15471..888ce14 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -2529,7 +2529,7 @@
                  android:hasCode="false"
                  android:label="@string/android_system_label"
                  android:allowClearUserData="false"
-                 android:backupAgent="com.android.server.SystemBackupAgent"
+                 android:backupAgent="com.android.server.backup.SystemBackupAgent"
                  android:killAfterRestore="false"
                  android:icon="@drawable/ic_launcher_android"
                  android:supportsRtl="true">