[jdk11u-dev] RFR: 8303482: Update LCMS to 2.15

[Goetz Lindenmaier]

I backport this for parity with 11.0.20-oracle.

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Commit messages:
 - Backport c073ef2ed59483c8dccec9fcac930c862885ff91

Changes: https://git.openjdk.org/jdk11u-dev/pull/1834/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1834&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303482
  Stats: 113 lines in 29 files changed: 48 ins; 12 del; 53 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1834.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1834/head:pull/1834

PR: https://git.openjdk.org/jdk11u-dev/pull/1834