A few small fixes to main.py from a previous code review.
A few small fixes to main.py from a previous code review.

R=maruel@chromium.org
BUG=

Review URL: https://codereview.chromium.org/10939034

git-svn-id: 8fa0a038c61565a87d0885d584517a2e12819dac@157768 0039d316-1c4b-4281-b951-d872f2087c98

luci/luci-py,pombreda/swarming,luci/luci-py,madecoste/swarming,luci/luci-py,madecoste/swarming,madecoste/swarming,pombreda/swarming,madecoste/swarming,luci/luci-py,pombreda/swarming,pombreda/swarming