Summary: See PHI385. Ref T13054. Ref T13083. The dashboard "arrange" operations (add, remove, move) rely on doing `$dashboard->setThing(...)` and then applying transactions. This no longer works after the read locking change from T13054. To make this function again, just add an explicit `save()` after layout adjustment. This should be more nuanced eventually, but all arrange operations are nonfunctional in a corrupting way at HEAD of `master`/`stable`, so stop the bleeding first. Test Plan: - Created new empty and template dashboards. - Moved panels. - Added new and existing panels. - Removed panels. Maniphest Tasks: T13083, T13054 Differential Revision: https://secure.phabricator.com/D19123