Invoke perfprofd daemon (only for userdebug/eng builds).

Change-Id: Ifaabe32dda6db249efc62c5db3760e32295eb1a9
(cherry picked from commit d6544d2a405df4c6e1fb517b1038a3640ae5f095)
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 40cd070..02b3656 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -655,3 +655,11 @@
     class main
     disabled
     oneshot
+
+on property:ro.debuggable=1
+    start perfprofd
+
+service perfprofd /system/xbin/perfprofd
+    disabled
+    user root
+    oneshot