RFR: 8316557: Make fields final in 'sun.util' package [v2]

[Andrey Turbanov]

> A few classes in `sun.util` package have non-final fields which could easily be marked `final`.

Andrey Turbanov has updated the pull request incrementally with one additional commit since the last revision:

  8316557: Make fields final in 'sun.util' package
  
  rename 'firstDay' to 'firstDays' to match 'minDays' naming

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Changes:
  - all: https://git.openjdk.org/jdk/pull/15736/files
  - new: https://git.openjdk.org/jdk/pull/15736/files/26d00dcb..5db74105

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15736&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15736&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/15736.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15736/head:pull/15736

PR: https://git.openjdk.org/jdk/pull/15736