GitLab

This CL lets ArcVmClientAdapter start and stop new upstart jobs
arcvm-mount-myfiles and arcvm-mount-removable-media. They mount the
media directories (/media/removable and /home/chronos/user/MyFiles)
under /run/arcvm/media when a user signs in.
The directory /run/arcvm/media is supposed to have been exported to
ARCVM, and these jobs will make the media directories visible for ARCVM.

BUG=b:123377807
BUG=b:123641356
TEST=$ components_unittests --gtest_filter="ArcVmClientAdapterTest.*"
TEST=Start ARCVM from various states (using e.g. `pkill crosvm`,
TEST=`adb reboot`), then check the log /var/log/chrome/chrome and the
TEST=directory /run/arcvm/media. Confirm that the jobs always start
TEST=without errors, and the media directories are successfully mounted.

Change-Id: Ife673620b41f9b4e4cf72df29ce3ab59d4bbac7d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2266053
Commit-Queue: Youkichi Hosoi <youkichihosoi@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: Satoshi Niwa <niwa@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799681}