R1:8f715d8edf9d

Add a credential selection control to Passphrase

Summary: Ref T4122. Adds a control for choosing credentials.

Test Plan: See screenshots.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran, lsave

Maniphest Tasks: T4122

Differential Revision: https://secure.phabricator.com/D7617