juju-register does not remember controller

[Nicholas Skaggs]

After a controller has been set with juju-register, change-user-password dies with: no controller Please either create your own new controller using "juju bootstrap" or connect to another controller that you have been given access to using "juju register" It appears that juju is no longer tracking the current controller.

As seen in http://reports.vapour.ws/releases/issue/57b489fe749a5611d0fafc16. This behavior has started between commit 2f3dc472edc8825d0fdd5cf8683432c3820e5f99 and c143850d69db1fccf7cd5dc3ecb6ab80739dbd61.

I suspect the c143850d69db1fccf7cd5dc3ecb6ab80739dbd61 commit is the cause of the issue. Either the test itself is using a model connection (and thus this fails?), or something is wrong within juju-core itself.