Dataverse ~5.14 appears to switch behavior from sending an empty file persistentId when one doesn't exist (draft or not using file pids). This PR makes the core retriever script check for both cases when deciding what form of file retrieval URL to create in the header. Without this fix, opening a previewer in a separate page (the header isn't shown when the display is inline) causes an error when the file doesn't have a PID and it doesn't display the header or content.
Dataverse ~5.14 appears to switch behavior from sending an empty file persistentId when one doesn't exist (draft or not using file pids). This PR makes the core retriever script check for both cases when deciding what form of file retrieval URL to create in the header. Without this fix, opening a previewer in a separate page (the header isn't shown when the display is inline) causes an error when the file doesn't have a PID and it doesn't display the header or content.