RFR: 8261169: Upgrade HarfBuzz to the latest 2.8.0

[Phil Race]

Upgrade to harfbuzz 2.8

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Commit messages:
 - 8261169: Upgrade HarfBuzz to the latest 2.8.0

Changes: https://git.openjdk.java.net/jdk/pull/3826/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3826&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261169
  Stats: 13120 lines in 123 files changed: 7021 ins; 2757 del; 3342 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3826.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3826/head:pull/3826

PR: https://git.openjdk.java.net/jdk/pull/3826