crosperf: show the elapsed time for the running job.

BUG=chromium:564890
TEST=it shows the current running time for the running job.

Change-Id: I1203abcf4455d289b34f02cf542bd5dae62b8d0a
Reviewed-on: https://chrome-internal-review.googlesource.com/240881
Commit-Ready: Yunlian Jiang <yunlian@google.com>
Tested-by: Yunlian Jiang <yunlian@google.com>
Reviewed-by: Caroline Tice <cmtice@google.com>
Reviewed-by: Yunlian Jiang <yunlian@google.com>
Reviewed-by: Luis Lozano <llozano@chromium.org>
1 file changed