RFR: 8364687: Enable headless with -Dglass.platform=headless

Tue Aug 5 08:33:51 UTC 2025

Basically allow -Dglass.platform=headless to enable headless, not only -Dglass.platform=Headless.
This makes it consistent with other options (macosx, windows, linux, gtk and ios) as well was less error-prone for enabling it.

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Commit messages:
 - Allow headless (lowercase)

Changes: https://git.openjdk.org/jfx/pull/1864/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1864&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8364687
  Stats: 3 lines in 1 file changed: 3 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jfx/pull/1864.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1864/head:pull/1864

PR: https://git.openjdk.org/jfx/pull/1864