Retroactive update fails if File doesn't exists in the public folder (file could not be copied because it does not exist)

Attached patch that checks if file exists in the public folder before moving the file.

Hello.

+1 RTBC by me.
It's works as expected during condition about change any entity that has image in DB, but image doesn't available on server part.
Besides, I have tested work with images with using stage_file_proxy module.

In addition, I have created fork and MR.

Needs test