RFR: 8283715: Update ObjectStreamClass to be final [v2]

[Stuart Marks]

> Pretty much just what it says.

Stuart Marks has updated the pull request incrementally with one additional commit since the last revision:

  Adjust nonfinal CSMs and rework error reporting in CheckCSMs.java test

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8009/files
  - new: https://git.openjdk.java.net/jdk/pull/8009/files/4b9bf990..77b6d79f

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8009&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8009&range=00-01

  Stats: 8 lines in 1 file changed: 2 ins; 1 del; 5 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8009.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8009/head:pull/8009

PR: https://git.openjdk.java.net/jdk/pull/8009