Views block_content revision relation should have revision_user field

Problem/Motivation
If we create any view for "custom block" and try to reveal data about "custom_block_author" our best bet is to open up revision for this block_content, so we can fetch "revision_user" data from "block_content_revision" table. But when we use the relationship to add "block_content_revision" in the fields section we can not found "revision_user" data as one of the field data.

Proposed resolution
Create a views field which can expose "revision_user" data.