Auto-approve for repeat logins doesn't return sreg data

[Stuart Metcalfe]

When testing functionality on bug #121533 I ran into an issue. To reproduce:

1. Select 'sreg' (and default options) in the test consumer.
2. Choose the fields you want to return and continue back to the consumer.
3. Quickly repeat step 1
4. Note that "The server returned no Simple Registration data."

This is because our server code currently auto-approves logins to sites you've already logged in to in the current session within a defined period. The code which does this isn't aware of the new user-controlled sreg data. This affects untrusted consumers. I haven't checked with trusted consumers but that functionality hasn't changed.

[Dave Morley (davmor2)]

Passes on vps