RFR: 8341064: Define anchor point and index term for "wrapper classes"

[Joe Darcy]

The is the initial version of a PR to defined an anchor point and index term of "wrapper classes."

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Commit messages:
 - JDK-8341064: Define archor point and index term for "wrapper classes"

Changes: https://git.openjdk.org/jdk/pull/21215/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21215&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8341064
  Stats: 28 lines in 2 files changed: 8 ins; 0 del; 20 mod
  Patch: https://git.openjdk.org/jdk/pull/21215.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21215/head:pull/21215

PR: https://git.openjdk.org/jdk/pull/21215