RFR: 8261891: sanity/client/SwingSet/src/EditorPaneDemoTest.java fails with Metal API Validation

[Alexey Ushakov]

Refactored AA shader usage. Performed end of AAshader encoder for incompatible rendering modes

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Commit messages:
 - 8261891: sanity/client/SwingSet/src/EditorPaneDemoTest.java fails with Metal API Validation

Changes: https://git.openjdk.java.net/lanai/pull/201/files
 Webrev: https://webrevs.openjdk.java.net/?repo=lanai&pr=201&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261891
  Stats: 108 lines in 6 files changed: 47 ins; 51 del; 10 mod
  Patch: https://git.openjdk.java.net/lanai/pull/201.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/201/head:pull/201

PR: https://git.openjdk.java.net/lanai/pull/201