RFR: 8344314: Revert removal of jdk.internal.java.PreviewFeature.CLASSFILE_API

[Adam Sotona]

jdk.internal.java.PreviewFeature.CLASSFILE_API has been accidentally removed with JDK-8334714, however it should remain until used in bootstrap build.

Please review.

Thank you,
Adam

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Commit messages:
 - 8344314: Revert removal of jdk.internal.java.PreviewFeature.CLASSFILE_API

Changes: https://git.openjdk.org/jdk/pull/22150/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22150&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344314
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/22150.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22150/head:pull/22150

PR: https://git.openjdk.org/jdk/pull/22150