RFR: 8347063: Add comments in ClassFileFormatVersion for class file format evolution history

[Joe Darcy]

On Mon, 6 Jan 2025 18:26:54 GMT, Chen Liang <liach at openjdk.org> wrote:

> `javax.lang.model.SourceVersion` has a series of comments describing the new language features present in each source version. Similar comments for the `ClassFileFormatVersion` would be helpful, so readers no longer need to search through the JVMS to find changes in new versions.

Generally looks fine and the changes per release look plausible; I didn't double-check them.

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Marked as reviewed by darcy (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/22934#pullrequestreview-2532849326