Clean up site_hosts.py.

Miscellaneous cleanup to remove dead code and improve comments.

BUG=None
TEST=run bvt

Change-Id: I53716e59eae354fa6b9b4265492d36e04a4a5944
Reviewed-on: https://gerrit.chromium.org/gerrit/38335
Tested-by: Richard Barnette <jrbarnette@chromium.org>
Reviewed-by: Simran Basi <sbasi@chromium.org>
Commit-Ready: Richard Barnette <jrbarnette@chromium.org>
1 file changed