cros mod_image_for_factory: don't enable update engine for factory test images (TBR, ToT to factory)

mod_for_factory_scripts/200patchInitScript

Index: mod_for_factory_scripts/200patchInitScript
diff --git a/mod_for_factory_scripts/200patchInitScript b/mod_for_factory_scripts/200patchInitScript
index 422d8af92638987258a80b5174e673e452fb1945..7f6bc0c76d61ab19b7dc62b66b0e6cc40bd9b1e9 100755
--- a/mod_for_factory_scripts/200patchInitScript
+++ b/mod_for_factory_scripts/200patchInitScript
@@ -73,6 +73,17 @@ tail -n 48 -F /var/log/factory.log >/dev/tty3
 end script
 EOF
 
+if [ -r "${ROOT_FS_DIR}/etc/init/update-engine.conf" ]; then
+  patch -d "${ROOT_FS_DIR}" -Np1 <<EOF
+diff -Na -U 0 old/etc/init/update-engine.conf new/etc/init/
+--- old/etc/init/update-engine.conf	2010-08-05 16:32:55.000000000 -0700
++++ new/etc/init/update-engine.conf	2010-08-05 16:32:45.000000000 -0700
+@@ -8 +8 @@
+-start on starting system-services and started dbus
++start on never
+EOF
+fi
+
 if [ -r "${ROOT_FS_DIR}/etc/init/chrontel.conf" ]; then
   patch -d "${ROOT_FS_DIR}" -Np1 <<EOF
 diff -Nau old/etc/init/chrontel.conf new/etc/init/