Swap Repository Edit UI to new code

Summary:
Ref T10748. This needs more extensive testing and is sure to have some rough edges, but seems to basically work so far.

Throwing this up so I can work through it more deliberately and make notes.

Test Plan:
- Ran migration.
- Used `bin/repository list` to list existing repositories.
- Used `bin/repository update <repository>` to update various repositories.
- Updated a migrated, hosted Git repository.
- Updated a migrated, observed Git repository.
- Converted an observed repository into a hosted repository by toggling the I/O mode of the URI.
- Conveted a hosted repository into an observed repository by toggling it back.
- Created and activated a new empty hosted Git repository.
- Created and activated an observed Git repository.
- Updated a mirrored repository.
- Cloned and pushed over HTTP.
- Tried to HTTP push a read-only repository.
- Cloned and pushed over SSH.
- Tried to SSH push a read-only repository.
- Updated several Mercurial repositories.
- Updated several Subversion repositories.
- Created and edited repositories via the API.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10748

Differential Revision: https://secure.phabricator.com/D15842

src/applications/diffusion/controller/DiffusionRepositoryListController.php

@@ -15,16 +15,9 @@ final class DiffusionRepositoryListController extends DiffusionController {
   protected function buildApplicationCrumbs() {
     $crumbs = parent::buildApplicationCrumbs();
 
-    $can_create = $this->hasApplicationCapability(
-      DiffusionCreateRepositoriesCapability::CAPABILITY);
-
-    $crumbs->addAction(
-      id(new PHUIListItemView())
-        ->setName(pht('New Repository'))
-        ->setHref($this->getApplicationURI('new/'))
-        ->setDisabled(!$can_create)
-        ->setWorkflow(!$can_create)
-        ->setIcon('fa-plus-square'));
+    id(new DiffusionRepositoryEditEngine())
+      ->setViewer($this->getViewer())
+      ->addActionToCrumbs($crumbs);
 
     return $crumbs;
   }