Fix mock Site classes

I5e480be86a0b7b6a5907cf71690ba9ebed0b04b6 depended on Site having
_loginstatus, which was not added to the mock Site subclasses in the
test suite.

Change-Id: I94df9e30b328bfab6892954ba8d6c443efa33d49
Merge "Fix mock Site classes"