For consistency, we should go over all CDS warnings, convert them to UL and clean up as necessary.

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Most CDS warning message have been changed to use UL, but some have not:

$ java -Xshare:off -XX:ArchiveClassesAtExit=foo -version
Java HotSpot(TM) 64-Bit Server VM warning: -XX:ArchiveClassesAtExit is unsupported when base CDS archive is not loaded. Run with -Xlog:cds for more info.

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There are also old warning message that used to be prefixed with UseSharedSpaces. E.g.,

UseSharedSpaces: Checksum verification failed.

But when these were converted to UL, the "UseSharedSpaces" was left there by mistake:

[0.262s][info][cds] UseSharedSpaces: Checksum verification failed.