<AWT Dev> [jdk17] RFR: 8266079: Lanai: AlphaComposite shows differences on Metal compared to OpenGL

[Alexey Ushakov]

Implemented blit via compute kernel

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

Commit messages:
 - 8266079: Lanai: AlphaComposite shows differences on Metal compared to OpenGL

Changes: https://git.openjdk.java.net/jdk17/pull/62/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17&pr=62&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8266079
  Stats: 289 lines in 4 files changed: 288 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk17/pull/62.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17 pull/62/head:pull/62

PR: https://git.openjdk.java.net/jdk17/pull/62