Fix OAuth Client Authorization bugs
Summary: ajtrichards reported an error creating a brand new authorization. fixed that and generally made this flow work well
Test Plan:
- created a fresh test client
- noted "new=<PHID>" with appropriate highlighting
- visited http://phabricator.dev/oauthserver/auth/?client_id=PHID-OASC-jwgdrqdpzomtxyg3q3yf&response_type=code&scope=offline_access
- clicked "cancel", verified result
- clicked "approve", verfied result
- visited http://phabricator.dev/oauthserver/auth/?client_id=PHID-OASC-jwgdrqdpzomtxyg3q3yf&response_type=code&scope=whoami
- noted got the dialog
- noted that it had the union of desired and existing so user could update it properly! (NB - its up to the client to react to whatever specific scope(s) the user decides to grant)
- noted it actually updated when I hit "approve"
Reviewers: epriestley, ajtrichards
Reviewed By: epriestley
CC: aran, epriestley
Maniphest Tasks: T933
Differential Revision: https://secure.phabricator.com/D1775