• This extends @deprecated because the compiler's unused linting ignores items annotated with
• @deprecated.

@som-snytt would it be difficult for the unused-detection code to recognize @unused directly? otherwise it seems like piling hack upon hack. annotations extending each other seems weird to me, and hijacking @deprecated in this context was a hack in the first place

Although this solution has a certain elegance to it, superseded by #7623 which instead of piling hack upon hack, just shoves it off to one side and maybe spreads it around a little to make sure the garden is evenly fertilized.