FYI: 8242653: Lanai: SRC_OVER with extra alpha does not work for VI

[Alexey Ushakov]

Passed extra alpha to texture shader

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Commit messages:
 - 8242653: Lanai: SRC_OVER with extra alpha does not work for VI

Changes: https://git.openjdk.java.net/lanai/pull/27/files
 Webrev: https://webrevs.openjdk.java.net/lanai/27/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8242653
  Stats: 15 lines in 4 files changed: 3 ins; 3 del; 9 mod
  Patch: https://git.openjdk.java.net/lanai/pull/27.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/27/head:pull/27

PR: https://git.openjdk.java.net/lanai/pull/27