RFR: 8318364: Add an FFM-based implementation of harfbuzz OpenType layout [v6]

[Phil Race]

> 8318364: Add an FFM-based implementation of harfbuzz OpenType layout

Phil Race has updated the pull request incrementally with one additional commit since the last revision:

  8318364

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15476/files
  - new: https://git.openjdk.org/jdk/pull/15476/files/f6f2abf2..ee60f7e9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15476&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15476&range=04-05

  Stats: 17 lines in 2 files changed: 2 ins; 0 del; 15 mod
  Patch: https://git.openjdk.org/jdk/pull/15476.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15476/head:pull/15476

PR: https://git.openjdk.org/jdk/pull/15476