User.get_profile() has checks in place to make use of any profile

fetched along with the user via select_related() or

prefetch_related().
In the case where the cached profile result is a None, we were falling

back on default behavior based on the create_if_missing flag. This is

fine if the flag is True (we want to create) but if the flag is

False a redundant fetch would occur, which would likely still return a

None result.
This code now respects a None entry in the cache in this case,

returning the None directly without the extra fetch.
This will significantly speed up search indexing for users, which was

performing 4 queries per user.

Unit tests pass.
Built new unit tests (for an upcoming change) that found this issue and

verified the fix.