Field Page crashes if duplicate media items are formed

Problem/Motivation

Whenever a user inputs any media item that has the same name as a pre-existing media, the page /content/fields crashes.

Steps to reproduce

Upload a media item with a file, for example: example.txt. Give the media any name, e.g. Example. Upload another media item with the same file and same name, in this case, Example would be the title and example.txt would be the file. Then go to /content/files.

Proposed resolution

Add a conditional statement in file_entity that allows the file size to be null.

Remaining tasks

Sending a merge request

User interface changes

None

API changes

None

Data model changes

None