Add support for top-app stune group.

bug 29512132

Change-Id: I41ec2dd80a469309f48dbb59fc27fbe43fcd67b3
diff --git a/rootdir/init.rc b/rootdir/init.rc
index da3b98b..32970e4 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -50,12 +50,16 @@
     mkdir /dev/stune
     mount cgroup none /dev/stune schedtune
     mkdir /dev/stune/foreground
+    mkdir /dev/stune/top-app
     chown system system /dev/stune
     chown system system /dev/stune/foreground
+    chown system system /dev/stune/top-app
     chown system system /dev/stune/tasks
     chown system system /dev/stune/foreground/tasks
+    chown system system /dev/stune/top-app/tasks
     chmod 0664 /dev/stune/tasks
     chmod 0664 /dev/stune/foreground/tasks
+    chmod 0664 /dev/stune/top-app/tasks
 
     # Mount staging areas for devices managed by vold
     # See storage config details at http://source.android.com/tech/storage/