Improve UX and messaging for certain errors when landing revisions

Summary:
Ref T9994.

  - Allow errors to be dismissed.
  - Tailor messaging for closed/abandoned revisions.
  - Reduce scare messaging on land dialog, since it's not really that scary anymore.

Test Plan:
  - Dismissed errors.
  - Hit new warnings.
  - Wasn't as scared when landing.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T9994

Differential Revision: https://secure.phabricator.com/D14886

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -1047,6 +1047,7 @@ final class DifferentialRevisionViewController extends DifferentialController {
     $operations = id(new DrydockRepositoryOperationQuery())
       ->setViewer($viewer)
       ->withObjectPHIDs(array($revision->getPHID()))
+      ->withIsDismissed(false)
       ->withOperationTypes(
         array(
           DrydockLandRepositoryOperation::OPCONST,