RFR: 8335059: Consider renaming ClassLoaderData::keep_alive [v3]

[Coleen Phillimore]

> How does this rename look?  Instead of ClassLoaderData::keep_alive() and a _keep_alive refcount, it's been renamed to _strongly_reachable and is_strongly_reachable().
> Tested with tier1 on Oracle supported platforms.

Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:

  Remove comments, update comment, fix compliation error.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20408/files
  - new: https://git.openjdk.org/jdk/pull/20408/files/38f036f7..4cd8e222

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20408&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20408&range=01-02

  Stats: 5 lines in 2 files changed: 1 ins; 2 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20408.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20408/head:pull/20408

PR: https://git.openjdk.org/jdk/pull/20408