Pass recently applied transactions to HeraldAdapters

Summary: Ref T9851. See T9860. This adds a missing capability to custom HeraldActions, to pave the way for removing the obsolete/undesirable WILLEDITTASK and DIDEDITTASK events.

Test Plan: See T9860 for a replacement action.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T9851

Differential Revision: https://secure.phabricator.com/D14575