Fix another "reply" issue with inlines showing up on the wrong side

We can just trust the "reply" value on the server, since inlines never port from old to new or vice versa.

Auditors: btrahan

src/infrastructure/diff/PhabricatorInlineCommentController.php

@@ -266,6 +266,8 @@ abstract class PhabricatorInlineCommentController
       // comment appears on. This is expected in the case of ghost comments.
       // We currently put the new comment on the visible changeset, not the
       // original comment's changeset.
+
+      $this->isNewFile = $reply_comment->getIsNewFile();
     }
   }