[jdk15u-dev] RFR: 8282280: Update Xerces to Version 2.12.2

[Yuri Nesterenko]

Clean backport this for consistency and parity with major releases.
Tier2 tests run fine.

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Commit messages:
 - Backport 72bd41b844e03da4bcb19c2cb38d96975a9ebceb

Changes: https://git.openjdk.org/jdk15u-dev/pull/237/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk15u-dev&pr=237&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8282280
  Stats: 310 lines in 17 files changed: 296 ins; 3 del; 11 mod
  Patch: https://git.openjdk.org/jdk15u-dev/pull/237.diff
  Fetch: git fetch https://git.openjdk.org/jdk15u-dev pull/237/head:pull/237

PR: https://git.openjdk.org/jdk15u-dev/pull/237