Add an "Always match" mode to conditions.

Review Request #8424 — Created Sept. 21, 2016 and submitted — Latest diff uploaded


Conditions are great, but sometimes you don't actually need them. Perhaps
someone is writing an integration with a chat service where they don't actually
care to limit which items get posted. Or an automatic review tool which should
run against all review requests, no matter what.

This change adds a new "Always match" mode to ConditionSet. When this is
chosen, the conditions list is hidden entirely, and the condition set will
always evaluate as matching.

This also contains a small fix to allow the condition form to load even when
the default value is empty (None).

  • Ran unit tests.
  • Used this in conjunction with a test integration.