[lworld] RFR: 8295086: [lworld] follow-up for JDK-8288131 [v4]

[Vicente Romero]

> code related to primitive classes needs to be hidden behind the -XDenablePrimitiveClasses flag, this work is a follow-up of JDK-8288131. Hiding this remaining code behind the flag is not absolutely necessary as it probably won't be executed anyways but it will make easier to located, and extract if needed, the code related with primitive classes only

Vicente Romero has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains five commits:

 - Merge branch 'lworld' into JDK-8295086
 - additional changes
 - following on with the changes after merge
 - Merge branch 'lworld' into JDK-8295086
 - 8295086: [lworld] follow-up for JDK-8288131

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Changes: https://git.openjdk.org/valhalla/pull/793/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=793&range=03
  Stats: 187 lines in 14 files changed: 63 ins; 26 del; 98 mod
  Patch: https://git.openjdk.org/valhalla/pull/793.diff
  Fetch: git fetch https://git.openjdk.org/valhalla pull/793/head:pull/793

PR: https://git.openjdk.org/valhalla/pull/793