[lworld] RFR: 8295086: [lworld] follow-up for JDK-8288131 [v5]

[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 seven commits:

 - Merge branch 'lworld' into JDK-8295086
 - more changes
 - 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=04
  Stats: 342 lines in 21 files changed: 62 ins; 176 del; 104 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