Remove direct reads of form state from main Inline client code
Ref T13559. Instead of directly reading form state, make all callers use the "active" state instead. The state reads the form.
No functional changes, just clarifying responsiblites.
Test Plan: Created inlines, etc. See followup changes.
Maniphest Tasks: T13559
Differential Revision: https://secure.phabricator.com/D21647