RFR: 8347433: Deprecate XML interchange in java.management/javax/management/modelmbean/DescriptorSupport for removal [v2]

[Kevin Walls]

> DescriptorSupport has a constructor and a method providing creation from, and export to, XML.
> 
> These are unused in the JDK and have no practical known examples of usage.  XML parsing is best done by an independent implementation, not this class.

Kevin Walls has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains eight additional commits since the last revision:

 - comments
 - Merge remote-tracking branch 'upstream/master' into 8347433_DescriptorSupport_deprecate_XML
 - (c)
 - typo
 - Merge remote-tracking branch 'upstream/master' into 8347433_DescriptorSupport_deprecate_XML
 - Also XMLParseException
 - RMMB comment update
 - Deprecate XML interchange in DescriptorSupport

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/23038/files
  - new: https://git.openjdk.org/jdk/pull/23038/files/f1aeaf95..1d236064

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23038&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23038&range=00-01

  Stats: 189272 lines in 4662 files changed: 93514 ins; 76111 del; 19647 mod
  Patch: https://git.openjdk.org/jdk/pull/23038.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23038/head:pull/23038

PR: https://git.openjdk.org/jdk/pull/23038