arc: Stop touching /dev/.arc_sensor_ready for container

This is no longer needed after ag/14541448

BUG=chromium:1163124
TEST=App can access sensor data

Change-Id: Id20657fdda8d9df6989473df9af93bfbb8c3bdad
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2896683
Commit-Queue: Ryo Hashimoto <hashimoto@chromium.org>
Tested-by: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
(cherry picked from commit 4a5871991a25427a5238b7c7225d872ec32560f4)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/3020344
Reviewed-by: Satoshi Niwa <niwa@chromium.org>
diff --git a/arc/container/scripts/arc-sensor.conf b/arc/container/scripts/arc-sensor.conf
index 6f866ae..ff0c42b 100644
--- a/arc/container/scripts/arc-sensor.conf
+++ b/arc/container/scripts/arc-sensor.conf
@@ -8,22 +8,6 @@
 start on started arcpp-post-login-services
 stop on stopped arcpp-post-login-services
 
-# The following environment variable is passed when this job is
-# started from arcpp-post-login-services.
-import CONTAINER_PID
-
-pre-start script
-  {
-    echo "Pre-start arc-sensor"
-    set -x
-
-    # Signal the container that sensor devices are ready.
-    # TODO(hashimoto): Remove this b/188167862
-    exec nsenter -t "${CONTAINER_PID}" --mount --user --uts --pid --ipc --net \
-        --cgroup --root --wd -- /system/bin/touch /dev/.arc_sensor_ready
-  } 2>&1 | logger -t "${UPSTART_JOB}"
-end script
-
 # This job does not have script/exec stanza, so it is considered running forever
 # once started. See: http://upstart.ubuntu.com/cookbook/#jobs-that-run-forever