[lworld] RFR: 8280194: Abstract classes that allow value subclasses should be marked ACC_PERMITS_VALUE (0x0040)

[Srikanth Adayapalam]

Mark abstract classes that qualify with ACC_PERMITS_VALUE flag.

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Commit messages:
 - 8280194: Abstract classes that allow value subclasses should be marked ACC_PERMITS_VALUE (0x0040)

Changes: https://git.openjdk.java.net/valhalla/pull/622/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=622&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8280194
  Stats: 273 lines in 16 files changed: 228 ins; 10 del; 35 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/622.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/622/head:pull/622

PR: https://git.openjdk.java.net/valhalla/pull/622