Silence errors in the polling handler.
Silence errors in the polling handler.

It's bound to happen.

R=csharp@chromium.org
BUG=

Review URL: https://codereview.appspot.com/108730047

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