Delete all "force chunking" file upload code

Summary: Ref T7149. This was just to make testing easier, but chunking substantially works now.

Test Plan: `grep`

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7149

Differential Revision: https://secure.phabricator.com/D12076

src/applications/files/controller/PhabricatorFileDropUploadController.php

@@ -42,9 +42,6 @@ final class PhabricatorFileDropUploadController
         'name' => $name,
         'contentLength' => $request->getInt('length'),
         'viewPolicy' => $view_policy,
-
-        // TODO: Remove.
-        // 'forceChunking' => true,
       );
 
       $result = id(new ConduitCall('file.allocate', $params))