[autotest] Allow buildbot to use -m to retry on rpc failure.

We've seen many golo rpc flakiness. This CL allows buildbot
to retry the rpc with -m command without re-creating the suite.

BUG=chromium:419991
TEST=Normal flow works:
run_suites.py -s dummy -b lumpy -i lumpy-paladin/R42-6811.0.0-rc3
              -p suites
TEST=Option -m works before the test finishes
run_suites.py -s dummy -b lumpy -i lumpy-paladin/R42-6811.0.0-rc3
              -p suites
Kill the process right away and run
run_suites.py -s dummy -b lumpy -i lumpy-paladin/R42-6811.0.0-rc3
              -p suites -m JOB_ID
TEST=Option -m works after the test finishes
run_suites.py -s dummy -b lumpy -i lumpy-paladin/R42-6811.0.0-rc3
              -p suites
Wait the process to finish and run
run_suites.py -s dummy -b lumpy -i lumpy-paladin/R42-6811.0.0-rc3
              -p suites -m JOB_ID

Change-Id: I82f15df5de9585b72df50ed33ba8fc90e66fc10b
Reviewed-on: https://chromium-review.googlesource.com/252221
Reviewed-by: Dan Shi <dshi@chromium.org>
Commit-Queue: Fang Deng <fdeng@chromium.org>
Tested-by: Fang Deng <fdeng@chromium.org>
1 file changed