crosperf: clean results_organizer.py

BUG=chromium:567921
TEST=it is lint clean now.

Change-Id: I0cf9445f5db822462c53d75a138e984070319714
Reviewed-on: https://chrome-internal-review.googlesource.com/241429
Commit-Ready: Yunlian Jiang <yunlian@google.com>
Tested-by: Yunlian Jiang <yunlian@google.com>
Reviewed-by: Caroline Tice <cmtice@google.com>
1 file changed