Make TestResultsServer pass chromium pylint

This no longer passes Blink pylint, but since i'll be deleting
this code and moving it to infra.git on my next commit, that doesn't
matter.

I'm just commiting this update to Blink so that others have an easier
time of rebasing their patches.  Maybe. :(

Whitespace changes will likely still invalidate all patches.

BUG=405385
TBR=ojan

Review URL: https://codereview.chromium.org/492583002

git-svn-id: svn://svn.chromium.org/blink/trunk@180627 bbb929c8-8fbe-4397-9dbb-9b2b20218538