Use ApiTestCase Login instead of our own

Change-Id: I435f0762e2c4ffa27df7338bfd92b33ecee462d8
REQUIRES : I6f79416e4580ed8b IN CORE <<<<<<-------
Seems silly to do soemthing agin here core already
nearly does for us..
More tidying up will come in further changes
Merge "Use ApiTestCase Login instead of our own"