Make it possible to create new tasks with Blender's policies

src/applications/maniphest/editor/ManiphestTransactionEditor.php

@@ -453,6 +453,17 @@ final class ManiphestTransactionEditor
     }
 
     if ($app_capability) {
+      // Special exception for Blender:
+      // We don't want users to modify someone's else task policy and we don't
+      // really want user himself to modifu policy. Additionally, we can't grant
+      // policy modification to just task author which makes it's tricky to create
+      // new objects.
+      // So we ignore edit policy for new objects.
+      if ($app_capability == ManiphestEditPoliciesCapability::CAPABILITY) {
+        if ($object->getPHID() == "") {
+          return;
+        }
+      }
       $app = id(new PhabricatorApplicationQuery())
         ->setViewer($this->getActor())
         ->withClasses(array('PhabricatorManiphestApplication'))