Fixing `CompactNumberFormat.clone()` to clone mutable reference objects. The bug was caused by accessing the shared objects concurrently which resulted in an illegal state on parsing. There are other reference fields that are shared, but the contents of those fields (such as prefix/suffix) are constants/read-only, so they may be shared.
------------- Commit messages: - initial commit Changes: https://git.openjdk.org/jdk/pull/27475/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27475&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8368328 Stats: 98 lines in 2 files changed: 97 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/27475.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/27475/head:pull/27475 PR: https://git.openjdk.org/jdk/pull/27475
