launch-on-reboot: Delete pre-existing startup scripts
launch-on-reboot: Delete pre-existing startup scripts

BUG=skia:

Review URL: https://codereview.chromium.org/1355163002

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot