Now depends on #4717.

Because views may not map 1-1 to FIRRTL targets and that annotations are so heavily exposed to the user (esp. via Stage/Phase), we have to generate a RenameMap for any views that are annotated. Previously, we couldn't know what views might be annotated (the .toTarget call is after Chisel elaboration) so we had to conservatively generate a RenameMap for all views that don't map 1-1. This is ludicriously expensive.

With #4643, we now require that annotations report what Data will be annotated up front, so now we only need to rename views that are actually annotated. Much more elegant and efficient at the cost of a minor API change.

I guess technically we shouldn't merge this until the deprecated APIs are removed... 🙈

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