Directly redirect to federated URL in direct editing

[juliushaertl]

When discussing with @tobiasKaminsky we figured out we could potentially send back the remote URL directly for direct editing to avoid a redirect

Potential patch needs testing:

diff --git a/lib/Controller/OCSController.php b/lib/Controller/OCSController.php
index 50504f15..cd0b65cb 100644
--- a/lib/Controller/OCSController.php
+++ b/lib/Controller/OCSController.php
@@ -119,15 +119,15 @@ class OCSController extends \OCP\AppFramework\OCSController {
                        }

                        $node = $nodes[0];
-                       if ($node instanceof Folder) {
+                       if (!$node instanceof File) {
                                throw new OCSBadRequestException('Cannot view folder');
                        }

                        $direct = $this->directMapper->newDirect($this->userId, $fileId);
-
+                       $federatedUrl = $this->federationService->getRemoteRedirectURL($node, $direct);
                        return new DataResponse([
                                'url' => $this->urlGenerator->linkToRouteAbsolute('richdocuments.directView.show', [
-                                       'token' => $direct->getToken()
+                                       'token' => $federatedUrl ?: $direct->getToken(),
                                ])
                        ]);
                } catch (NotFoundException $e) {