Fixed most of the warnings in experiment_runner.py.

Started by fixing a typo in one of my previous commits.
Fixed several warnings in the process.

BUG=None
TEST=simple run of crosperf.

Change-Id: I6c470cba52f47f52e63b94bc0171c2ef336b74de
Reviewed-on: https://chrome-internal-review.googlesource.com/235376
Commit-Ready: Luis Lozano <llozano@chromium.org>
Tested-by: Luis Lozano <llozano@chromium.org>
Reviewed-by: Yunlian Jiang <yunlian@google.com>
1 file changed