Search tests which used on-the-fly indexing were hitting deadlocks under the new haystack version. The problem here was that our indexing templates were calling `get_profile`, which would end up creating new profile objects if they didn't already exist. This would attempt to write from inside the indexer stack, which would hit a lock. I've added a new helper that can check if a profile is public without creating ones that don't exist. Other related code has been updated to use this new helper appropriately instead of reinventing the wheel. Testing Done: Ran unit tests.